Silencer FAQ (work-in-progress)

General silencer discussion. If you want to talk about a specific silenced rifle or pistol, it is best to do that in the rifle or pistol section for that brand.

All NFA laws apply.

Moderators: mpallett, mr fixit, bakerjw, renegade

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TROOPER
Silent But Deadly
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Location: Augusta, Georgia

Silencer FAQ (work-in-progress)

Post by TROOPER »

For Starters
FS1 - Is it legal to own a silencer?
FS2 - Why own a silencer?
FS3 - How do I buy a silencer/suppressor?
FS4 - What is the difference between a 'silencer' and a 'suppressor'?
FS5 - Who can buy a silencer?
FS6 - Can I shoot other cartridges calibers through the same silencer? I only want to buy one silencer and use it on multiple guns.

Legal
L1 - How do I handle legal challenges to my suppressor ownership?
L2 - Does purchasing a silencer enable the ATF to search or inspect my residence without a warrant?
L3 - Where do I have to keep my paperwork?
L4 – Where do I have to keep my suppressor?
L5 - Who can use my suppressor?
L6 - Who has the authority to inquire about documentation?
L7 - Can I legally make my own suppressor?
L8 - Can I 'write-off' the $200 tax stamp for tax purposes?
L9 - I have a Top Secret Clearance! Will this shorten the time for my background check?
L10 - I see advertisements or auctions for "solvent traps". What's this about?
L11 - Why do some people use a "Trust"? (This question-and-answer needs updating)
L12 - What is a "Form 1" a "Form 3" and a "Form 4"?

Practical
P1 - How do I clean my suppressor?
P2 - Can I shoot hollow-points through my suppressor?
P3 - Can I shoot .22 LR through my 5.56 suppressor?
P4 - Do I need special ammunition for my silencer?
P5 - Is there any specialty ammunition specifically for silencers?
P6 - Is there any ammunition specifically to avoid in silencers?
P7 - What is shooting "wet"?

General
G1 - What is the quietest possible setup?
G2 - What is subsonic? What is trans-sonic?
G3 - What is a "Nielson Device"?
G4 - Which Firearms require a Nielson Device?
G4.5 - What if I use my silencer with Nielson Device on a fixed barrel?
G5 - What is "First Round Pop"?
G6 - What is "Blowback"?
G7 - Can I put a suppressor on this firearm?
G8 - What is the best suppressor for <insert caliber>?
G9 - My 22 LR rifle and 22 LR pistol are both threaded 1/2 x 28, but the threads are different!
G10 - Why are silencers always so long and skinny? I want one short and wide!
G11 - All things being equal, what is quietest to suppress, 357, 44, or 300 BLK?

For Starters

FS1 - Is it legal to own a silencer?
In some states the answer is "yes", in other states the answer is "no". As of 2/23/2014, the following states/districts prohibits them: California, Delaware, Hawaii, Illinois, Iowa, Massachusetts, Minnesota, New Jersey, New York, Rhode Island, and the District of Columbia. More states allow silencers than prohibit them. Laws are subject to change, so please research your individual state before proceeding.

FS2 - Why own a silencer?
It makes the operation of your weapon quieter. In some instances, the operation can be so thoroughly reduced that hearing protection is no longer necessary. In some states, hunting is permitted with a silencer and there may be advantages to a shot which - while still audible - is less disruptive to the shooter or the environment.
A suppressor will act, in part, like a muzzle-brake by retarding the violent forward expulsion of gas particles, thus reducing felt recoil impulse.
Suppressing your weapon will often make the overall shooting experience more pleasant, especially in prolonged sessions.

FS3 - How do I buy a silencer/suppressor?
There are two ways to start this process. One method is to find the specific make and model that you prefer from a stocking dealer located anywhere in the US (a recommended dealer section is included in the Board Index of this forum). Purchase from that dealer and have them ship the item to a LOCAL, in-state class III dealer who will then walk you through the remainder of the transaction.
A second method is to skip the stocking dealer and go straight to a LOCAL, in-state class III dealer and choose from among what that dealer has in their immediate inventory.
After either of the first two steps, the LOCAL, in-state class III dealer will help you with the paperwork - called a "form 4" - and submitting it, along with a check for $200, to the ATF. After a period of time ranging from several months to a little over a year, the class III dealer will call you and tell you that you may come and retrieve your silencer/suppressor.

FS4 - What is the difference between a 'silencer' and a 'suppressor'?
The words are synonyms from a legal standpoint in that the BATF does not recognize a distinction between their usage. Some people argue that "silencer" is incorrect since the shot is not technically silenced. Others argue that the original Maxim patent is for a "silencer". Outside of the legal realm, the silencer/suppressor community will often refer to a silencer as a "can". In different regions of the world they are also referred to as "muffler" or "moderator", although neither term is commonly used within the United States.

FS5 - Who can buy a silencer?
Assuming your state does not prohibit ownership, then the only other criteria is a non-felon who is 21. Essentially, if you can purchase a handgun in a silencer-friendly state, you may purchase a silencer.

FS6 - Can I shoot other cartridges & calibers through the same silencer? I only want to buy one silencer and use it on multiple guns.
Yes-and-no. Cartridges and pressures vary enough that a simple answer isn't possible. You must always consult the manufacturer's recommendations for your individual silencer. That said, many manufacturers do list the calibers and cartridges which may safely be used with their particular silencers. For example, the AAC Element is listed as being safe for .22 LR, .17HMR and .22Magnum hosts.
One of the challenges of using one silencer for multiple hosts is mounting the silencer since the cartridges - for example 9mm and 45 ACP - may have different threaded mounts. Again, using AAC as an example, and from their website, "For multi-caliber use, pistons are available in the most common 9mm and .40 thread patterns to allow use of the Ti-RANT 45 on hosts in those calibers." However, generally speaking, the best performance will come from using a silencer for the cartridge it was designed for.


Legal
Obligatory disclaimer: the following information is delivered in good faith, however, if it is wrong, it will be you that suffers. Ultimately, it is your responsibility to understand the law and its nuances sufficiently to adhere to state and local regulations.

L1 - How do I handle legal challenges to my suppressor ownership?
If a non-LEO range officer approaches you and demands to see your paperwork, you are not obligated to produce, however, you will most likely be asked to leave. Many silencer users CHOOSE to comply, and merely produce either the paperwork or a copy of the paperwork. Many, many times a silencer user will shoot a session unchallenged even though the range safety officer was aware of the silencer use, but the range officer knew that the items were legally viable within the region and instead did not challenge at all. This is the most common situation.
If a law enforcement officer (LEO) challenges you, the most common response is to produce the requested paperwork. Quite often this will satisfy the situation and it will be completely diffused. However, there have been limited instances where the officers did not fully understand the legalities of his/her region and it took additional time and officer-superior communication to resolve the situation. If this happens, remain calm and understand that you have broken no laws.
A different school of thought is held by some silencer users that the paperwork is a tax document, and therefore out of the jurisdictional purview of the responding police officer. Unfortunately, there are few, few, stories of how such challenges and subsequent noncompliance (legal or otherwise) were resolved.

L2 -Does purchasing a silencer enable the ATF to search or inspect my residence without a warrant?
No. There is a persistent rumor that owning a silencer by default enables the ATF to search your house at their discretion. The ATF are permitted (with provisions) to inspect an FFL's place of business. The rumor probably started due to certain smaller FFLs operating out of their homes' garages, which lead to the myth that anyone with an NFA item such a silencer could also be searched or inspected without a warrant.

L3 - Where do I have to keep my paperwork?
Because the ATF is extremely reluctant to issue new paperwork to replace lost paperwork, it is critical to maintain the originals. Many individuals keep their Form 4 at home either in their gun safe, or a fire safe. Furthermore, the documents will contain sensitive personal information which should be protected (identity theft hazard).
Simultaneously, it is possible and common for the legality of your suppressor/silencer to be challenged in public both by non-LEO range officers or by local police officers themselves. As such, some people keep their paperwork with their suppressor so that they can verify legal ownership as necessary. Others keep photocopies of the information so that the originals remain secure elsewhere.

L4 - Where do I have to keep my suppressor?
It's legally a firearm so the requirements of securing firearms in any local jurisdiction apply with regard to securing NFA devices. In short, to satisfy the ATF, the registered transferee must not facilitate an illegal transfer.
It has been posited before that a cable lock run through the bore of a suppressor by the registered transferee where only the registered transferee has the means to unlock the device might be sufficient to establish "control" of the device even if another has "possession". This would be similar to the NFA being secured in a portable safe (<oxymoron) or the NFA being secured in a safe on premises accessible to non-transferees.

If you live at home alone or everyone in your household is a registered tranferee for the device and there are no local jurisdictions requiring the device to be secured when not in use then you can keep your NFA on the coffee table 24/7.

L5 - Who can use my suppressor?
Short answer, at the range anybody.
Long answer, anyone may use a NFA device in any jurisdiction where the use of the device is legal within the controlling presence of the legal entity registered as the transferee. The key element here is the registered transferee must maintain control of the of the device so as not to constitute an illegal transfer. This does not necessarily mean the registered transferee must maintain line of sight or a physical connection with either the NFA or the "guest" user. It has been posited that a non-transferee can reasonably expect to use a NFA on 500 acres of private property where the registered transferee is present but that is not the same as a non-transferee using a NFA on 500 acres of public land where the registered transferee is "around somewhere".

L6 - Who has the authority to inquire about documentation?
The three most common entities who will inquire are the non-LEO, non-employee, fellow customer/shooter.... the acting representative of the property at which you are using the silencer, specifically a Range Safety Officer... and the Law Enforcement Officer (LEO). How you handle a non-employee, non-LEO is your discretion. How you handle the employee who is non-LEO is also your discretion, although this entity does have the authority to order you off of the premises. The third entity has still greater authority, and since it is generally understood that an UNREGISTERED silencer/suppressor is illegal, proving that yours IS registered may be to your advantage. It should be noted that many - probably MOST - suppressor owners do comply with LEO paperwork requests.
Please do note that the list above is the common list, but NOT a comprehensive list, and additional agents or entities may inquire into your documentation.

L7 - Can I legally make my own suppressor?
Yes. The proper paperwork to submit is a "Form 1" and requires ATF clearance to proceed. A more in-depth discussion and "how-to" can be found here.

L8 - Can I write-off the $200 tax stamp for tax purposes?
No.

L9 - I have a Top Secret Clearance! Will this shorten the time for my background check?
No. A number of members on this board have claimed to hold security clearances and have indicated that their approval wait times are no different than anyone else. It is possible that some people claim to have a security clearance on the internet without actually having one. However, in the "wait-tracking-thread", while some times are shorter than others, none seem to be out of step; IE, those who start the process at the same time with the same approver, tend to end at about the same time.

L10 - I see advertisements or auctions for "solvent traps". What's this about?
Unfortunately, the moniker "solvent trap" may mean a few things, but if you're reading about it here on this forum, that means you think it is a silencer. Well, it is a silencer. In all likelihood, it's an unregistered silencer, and you can expect life-changing legal repercussions if you purchase it off of EBay or Craig's List or Soldier-of-Fortune or wherever you saw it. If you live in the US, avoid it.

Does it work? It may or may not work, but intent is what the government prosecutor will be looking for, and to add insult to injury, you may end up in prison for a silencer that doesn't work well.

L11 - Why do some people use a "Trust"?
There are two dominant reasons to use a Trust. The first and primary reason is that the individual lives in an area where the local law enforcement officer (LEO) is not supporting of NFA items such as silencers, transferable machine guns, or short-barreled rifles (SBR). In which case, by using a Trust, the individual is able to avoid having to have their LEO sign-off on the matter.

Originally, the LEO sign-off was to prevent individuals who are under investigation for a crime from acquiring an NFA object. A NICS background check won't uncover if a person is under investigation, only actual records. Since a Trust cannot be under investigation for committing a crime, it follows that a Trust will not need an LEO sign-off or finger-prints.

The secondary reason for using a Trust is that the Trust-holder can assign "trustees" who may then have more unfettered access to the items on the Trust. Although this is a distant motivation for establishing a Trust.

Note: if you have a Trust set up, and you eventually have an SBR made, then the name of the Trust will be what is engraved on the SBR. It is therefore in your interest to avoid overly long Trust names, while simultaneously embracing awesome names, IE: "Zombie-Megatron-Space-Ninja-Pirate-Trust".

L12 - What is a "Form 1" a "Form 3" and a "Form 4"?
Form 1 -- This form is to allow the end-user the ability to manufacturer an NFA item such as a silencer, an SBR (short-barreled rifle), or an SBS (short-barreled shotgun).

Form 3 -- This form allows an FFL/SOT to transfer an NFA item, such as a silencer, to another FFL/SOT. Most people in the NFA world will never have any use for this form.

Form 4 -- This form allows for the transfer of an NFA item, such as a silencer, from an FFL/SOT - usually just called a "Dealer" or "Class III" - to an end-user. This is the most common method of acquiring a silencer: you fill out a form 4 and send it off to the ATF with a check in order to transfer the silencer from the dealer to you.



Practical

P1 - How do I clean my suppressor?
Many centerfire rifle suppressors do not need to be cleaned due to the high pressure nature of the cartridge. This is often true for centerfire pistol silencers as well. However, rimfire suppressors - regardless of pistol or rifle host - WILL become excessively clogged and dirty over time, and as such, will suffer gradual loss of suppression, although it should be noted that this is a long-term process. As a result, conventional wisdom recommends the purchase only of "user-serviceable" rimfire silencers since a "sealed can" will have a finite number of shots built in to it until the manufacturer, or competent machinist, adequately services the suppressor.
It should be noted that cleaning for "user-serviceable" cans is material specific if the user intends to use chemicals. However, for all "user-serviceable" silencers, a copper wire brush is acceptable just as one would clean a fouled barrel.

P2 - Can I shoot hollow-points through my suppressor?
Yes.

P3 - Can I shoot .22 LR through my 5.56 suppressor?
It is very strongly recommended that you not do this. While it is true that any 5.56 silencer can safely handle the pressures associated with a .22 LR, the problem is that .22 LR is very dirty, and leaves a lot of carbon and lead residue inside of a silencer. After enough of this, the internal volume of the silencer is reduced to such a point that when the user switches back to the higher-powered 5.56 NATO, the pressure spikes to unsafe levels and may result in a catastrophic failure.
Please note that this procedure is safe if the manufacturer of that particular silencer states that it is.

P4 - Do I need special ammunition for my silencer?
Ammunition that does not exceed the speed of sound will be the quietest. This ammunition is referred to as "subsonic". Some calibers are subsonic in almost all instances, such a 38, or 380. Other calibers are sometimes subsonic, and sometimes supersonic, depending on loading. Specifically 9mm, 40 S&W, and 45 ACP. For all three, the heaviest factory loadings will typically be subsonic out of pistol-length barrels. But all three may also be supersonic if used in their lightest factory weights, and therefore not as quiet when shot through a silencer.
However, it is not necessary to use specialty ammunition -- merely a caliber determined safe by the silencer manufacturer, and within SAAMI limits (anything factory). Bottom line: if you have a 9mm silencer, you can shoot 9mm through it whether it's supersonic or not. Same for 45 ACP and any other caliber.

P5 - Is there any specialty ammunition specifically for silencers?
There are three basic types of specialty ammunition.
1 - The first type is merely marked as “suppressor ammunition” by virtue of the fact that it is subsonic in most hosts. An example is certain 9mm marked as “silencer ammunition” when in reality it has no extra manufacturing to differentiate it from ordinary 147 gr 9mm – which will always be subsonic out of a standard sized handgun. It is true that it is good for use on a silencer, but its results will not be distinguishable from ordinary 147 gr without any ‘silencer’ markings on the box.

2 - The second type of specialty ammunition is one in a common caliber that is somehow different from ordinary loadings, although the chambering remains the same. Aguilla SSS 22 LR is a 60 gr rimfire which is significantly different from other 22 in that ordinary 22 LR will typically top out at a weight of 40 gr. GemTech also makes specific 22 LR ammunition which has both a reduced powder charge, but also a heavier than normal 42 gr weight. Fiiochi, as well as IMI, both make a 158 gr 9mm. These are different specifically because their specifications fall outside of the normal range for their respective caliber.

3 - The third type of ammunition is a cartridge which was made specifically for silencer use as opposed to being incidentally good in the way that 147 gr 9mm is. The “Whisper” line of cartridges, and the 300 Blackout (300 BLK) are specifically made to provide top-tier silencer performance.

P6 - Is there any ammunition specifically to avoid in silencers?
Yes: "WinClean" ammunition has been reported to have a sort of sand-blasting effect on the interior of silencers, and may result in a markedly shorter lifespan of the unit. Also, unjacketed lead bullets may leave deposits inside of silencers that may shorten the life of the unit. It is for this reason that many of the top-of-the-line rimfire suppressors are take-apart / user-serviceable specifically to counter this leading effect. In centerfire silencers, there have been mixed reports and speculation advising against this activity.

P7 - What is shooting "wet"?
Shooting "wet" means that the user has put a small amount of fluid - usually water, but sometimes 'pulling gel' or white lithium grease - into the silencer and agitated the unit in order to make as much of the surfaces wet as possible. Due to the ideal gas law - PV=nRT - a decrease in temperature due to the heat of vaporization will necessarily lead to a reduction in pressure on the other side of the equation. This can make a notable difference in sound reduction. You must consult your manufacturer to determine if this is a safe practice for your particular silencer, since the addition of a non-compressible liquid necessarily reduces the amount of internal volume, which could lead to unsafe pressure spikes with certain cartridges. However, it is generally recognized as a safe practice with rimfire and pistol-caliber silencers, and always with very small amounts of fluid.


General

G1 - What is the quietest possible setup?
It is generally agreed upon that a bolt-action rifle chambered in 22 LR, shooting subsonic ammunition, through an integral silencer (a silencer which is built into the firearm and is not removable), wet.... will be the current quietest setup.

G2 - What is subsonic? What is trans-sonic?
Subsonic means "less than the speed of sound". In feet-per-second, this works out to around ~1,000 FPS and up to ~1,100 FPS. The higher number is generally the more accurate number, but temperature, humidity, and height above sea level all come in to play. It is generally regarded that within the continental US, if the bullet is traveling at 1,000 FPS or less, it will be subsonic.
Trans-sonic refers to a particular phenomenon whereby even though the bullet itself is traveling at less than the speed of sound, the air itself goes supersonic as it moves around the bullet. People who are unaware of this phenomenon may be confused if they are using a chronograph, but are still hearing the tell-tale sounds of super-sonic crack.

G3 - What is a "Nielson Device" or "booster"?
A "Nielson Device" - or "booster", which is the exact same thing - is a type of coupling device which helps to ensure reliable cycling for silencers mounted on Browning-style actions - also called "tilt-barrel" actions. In a pistol such as a GLOCK, if the user locks the slide to the rear, it will be clear that the barrel is tilted slightly upward, and is no longer parallel with the frame. Since the barrel tilts up during any normal cycle from a gunshot, the added weight of a silencer on the barrel might retard the ability of the barrel to tilt upward, thus causing FTFs and possible FTEs. A Nielson Device enables the silencer to quickly de-couple so that the barrel can tilt normally momentarily without also lifting the weight of the silencer.

G4 - Which firearms require a Nielson Device?
Essentially any firearm that does not have a fixed barrel can benefit from a Nielson Device. Therefore rifles are best without a Nielson Device. Certain fixed-barrel handguns are best without a Nielson Device. Furthermore, many "micro" or "compact" suppressors do not require a Nielson Device since their weight and length are reduced enough that the extra weight placed on the barrel is insufficient to adversely affect reliability.

G4.5 - What if I use my silencer with Nielson Device on a fixed barrel?
The typical situation where this would occur is if, for example, you take a 9mm silencer with booster off of a GLOCK and then immediately screw it on to a 9mm rifle without removing the booster. It has been suggested that this is bad practice since the silencer will still have the ability to move and shift with shots, and may cause a 'jackhammer' type of effect on the threading as a result. It is for this reason that many booster'ed silencers also have the option of utilizing a 'fixed spacer' specifically to avoid this wear-and-tear. Using a booster'ed silencer on a fixed barrel is considered unnecessarily risky to the threads.

G5 - What is "First Round Pop"?
First-Round-Pop, or FRP, is the louder-than-normal (for a suppressed shot) FIRST shot. This is considered to occur due to ambient Oxygen being combusted inside of the first chamber of the suppressor by unburned powder being ejected from the gun muzzle. The FRP is louder than the normal suppressed shot, but only subtly so, and it will not be confused with an unsuppressed shot. Certain designs or cans tend to have louder FRP than others -- see following question.

G6 - What is "blowback"?
Blowback, as it pertains to silencers/suppressors, refers to the phenomenon of increased soot, residue, or just gas being ejected from the rear of the gun - usually from the ejection port. This occurs because the muzzle of the gun will experience slightly increased levels of pressure when suppressed, and so the gas - which seeks the lowest pressure area - will partially vent through the rear of a gun. Bolt-actions are essentially immune from this phenomenon, while blow-back operated pistols (most 380s and many 22 pistols) will have the greatest increase in "blowback". Other operating systems such those used by ARs will have an increase, though not as severely as a blow-back operated firearm.
"Blowback" and "First Round Pop" are considered by some to be connected in that a silencer with a relatively large first chamber (blast chamber) will tend to have the most FRP, but a decreased Blowback.... and vice-versa.

G7 - Can I put a suppressor on this firearm?
Yes. Any gun can have a suppressor - any gun can be suppressed. However, certain firearms, such a shotgun, require such a specific and cumbersome type of suppressor that it becomes impractical, still not quiet enough, and is generally considered a poor idea although still technically feasible. Certain other types of firearms require additional care or modifications to accept a suppressor safely. For example, an AK-pattern rifle sometimes has issues (dependent on the manufacturer) with having a bore that is concentric with the barrel; therefore, if a silencer is attached, the bullet may strike or glance off a portion of the silencer as it exits. Other firearms, such as a Desert Eagle, have other issues such as altering the back pressure on a system that relies on siphoning off gas within a certain window of tolerances. Still other firearms simply do not suppress well for various other reasons.
The take-away on this question is that any firearm can be suppressed, although not all receive equal benefit from a suppressor. Please ask about your particular firearm, and you will receive viable feedback.

G8 - What is the best suppressor for <insert caliber>?
No make or model is given for the sake of this FAQ since the answer changes as newer models come to the market. However, this question is asked often enough that components of this question shall be addressed. This question is challenging based on your criteria; meaning that if absolute suppression is your primary objective, then there might be a specific answer. However, if cost, or weight, or materials, or appearance are your primary concern, then there are different "best options" for each of those respectively. No one unit is the best in every category... or no other make and model would ever be sold. When asking this question in an open forum to solicit responses on the current "best", it is important that the person asking understand that there are many metrics to rate a silencer, to include (in no particular order): cost, availability, weight, length, level-of-suppression, materials, fit-and-finish, appearance, ease-of-cleaning (when applicable), customer service, as well as specific answers related to your particular intended host, as certain suppressors have different characteristics related to FRP, blowback, full-auto capabilities, and level of suppression for pistol versus rifle. When asking this question, the more information you are able to share regarding the characteristics that are important to you, the better advice you will receive.

G9 - My 22 LR rifle and 22 LR pistol are both threaded 1/2 x 28, but the threads are different!
Many rifles with threaded barrels of 1/2 x 28 are cut so that the length between the muzzle and the 'shoulder' are longer than a similar threaded pattern for most pistols that are also threaded 1/2 x 28. In order to ensure the safest performance from your silencer, it should be screwed on until it butts up against the 'shoulder' of the threads, which should keep the silencer relatively stiffly attached to the barrel, as well as parallel to the bore. A silencer that is incompletely screwed on may have enough 'wobble' in it to risk the bullet striking or touching some portion of the silencer as it exits. In order to appropriately screw some silencers onto the longer version of 1/2 x 28 threads commonly seen on ARs as well as other rifles, the user should acquire a "Spacer" from a reputable silencer company. These items are not legally controlled, and so can be purchased with minimal wait time and without legal procedure. A spacer will effectively move the 'shoulder' forward, and still allow the silencer to be screwed on to the appropriate level of tightness, thus ensuring a relative stiffness of connection between silencer and barrel.
It has been noted that simply using a washer obtained from a hardware store may produce poor results since these mass-produced washers will lack the necessary tolerances to ensure -- once tightened -- that the bore of the suppressor remains parallel to the bore of the barrel.

G10 - Why are silencers always so long and skinny? I want one short and wide!
There are three key factors which influence the efficacy of a silencer: the internal volume of the silencer, the number of baffles, and the design of the individual baffles.
According to an industry professional, "The main reason you don't see a ton of cans like this is because in terms of performance, diameter (volume) is no replacement for length and additional baffles. The 'task' of the can is to strip away gas from the bore, you need baffles along the path of the gas to accomplish this. You end up with a can that is heavier for a given length, and not as efficient as a slightly longer one. Volume inside the can plays a part (why we don't see 1" diameter rifle cans), but it's secondary to length."

G11 - All things being equal, what is quietest to suppress, 357, 44, or 300 BLK?
For this question, assume subsonic loadings are used, and in equal length barrels. In which case, the only difference would be the bore-hole of the silencer. Therefore, the caliber that required the least amount of bore diameter through the silencer would be the quietest. For best suppression, the baffles must strip away gas as described in question G10 - but this process is hindered by a large hole through the middle of the silencer which the bullet must travel through which the gas may also travel through. It is for this reason that - all things being equal - smaller diameter calibers suppress better than larger diameter calibers.
Last edited by TROOPER on Sun Jan 17, 2016 10:03 am, edited 47 times in total.
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bakerjw
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Re: Silencer FAQ (work-in-progress)

Post by bakerjw »

A special thanks to Trooper for putting all of this information together in one place. If you have a question that isn't answered, you can post it here and it will be added if necessary.
July 5th, 2016. The day that we moved from a soft tyranny to a hard tyranny.
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TROOPER
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Re: Silencer FAQ (work-in-progress)

Post by TROOPER »

Thanks, Baker, but it is a group-effort for sure.

Speaking of which... I'm always soliciting advice on any answers already given to see if they can be improved, or repaired in the event of grammatical or technical errors. Also any new suggestions are welcome for subject matter. Dissenting opinions are also welcome, as the FAQ is about better informing shooters new to silencers - so if there's two different groups of people that approach a matter from two different methods of thoughts, share! Both sides will be given representation so that new people will have a deeper pool of knowledge with which to make their way through the NFA waters.
cyclone72
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Re: Silencer FAQ (work-in-progress)

Post by cyclone72 »

How bout common/specific trust questions (not unless already posted). I just started my very first trust and so far it has been a month since I bought the can and my Form 4 is still sitting on my computer desk along with last years T&A calendar. I'm still trying to figure out the paperwork. I would have gone individual but our NFA friendly sheriff recently passed, RIP. No one else does it so trust seemed the way to go.
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TROOPER
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Re: Silencer FAQ (work-in-progress)

Post by TROOPER »

I'm not sure how to handle this question. I bought both of my silencers via a 'revocable living trust', but I don't know that the process is black-and-white. I also thought I remembered hearing something about "trusts and corporations going away", but I don't know what came of that.

I can tell you my own story if it helps, but putting that level of near legal-advice in the main body of that FAQ... it's daunting. I suppose I could pepper it with caveats, warnings, and disclaimers.... but it would still feel wrong.

For the sake of posterity, here is my story:

I went to Staples / Office Max / Office Depot (I even saw this at a FedEx mail-and-fax type service shop recently) and purchased the "Socrates" brand of pre-made legal documents entitled a "Revocable Living Trust". Within that packet were maybe 5 different versions of the trust designed for people in slightly different situations - married, married with kids, divorced with kids, etc. I chose the version which fit my circumstances, and then tore them free from the packet. It was about 8 pages front-and-back, and there were several paragraphs per page with a blank at the bottom of each paragraph for the end-user to initial, with the back page having a line for a full signature, printed name, date, and notary public. I signed-and-initialed at my local bank which provided the complimentary notary service since I was an account holder.

After making many copies, I submitted the original to my Class III dealer who then submitted it with the check and the form 4 to the ATF. At some point you name the "revocable living trust", and I simply chose my full legal name, ex: Johnathon Quincy Doe. When the Class III submitted the form 4, he put the prospective owner as the "Johnathon Quincy Doe Revocable Living Trust." Of course I myself had to undergo a NICS (or similar) background check at the time it was necessary to take custody of the actual silencer, but the trust DID circumvent an uncooperative Sheriff, which was the goal.

I believe I paid ~$40 for the packet... perhaps $39.99 plus tax, or $34.99 plus tax... I just don't recall.

Here is a link to an Amazon product offering. And here is the best match to what I actually bought. Bear in mind that this was almost a decade ago, so there may be some minor changes to the product versus when I purchased it. I also note that the first Google hit goes to Office Depot, so that's most likely where I did purchase it, although I have seen similar pre-made legal forms available at similar office supply stores.

Here is the issue: there is open debate on this very website regarding the viability of these documents to withstand an ATF challenge in the event that they wish to make an issue out ownership. I can't say that the documents would stand up to a court case for the simple reason that my own have never been tested. I have not heard any anecdotes of other people getting in trouble with the ATF for using these similar types of pre-made forms either... so it is possible that the documents are perfectly sound. It's also possible that they're somehow legally flawed, yet simply haven't been tested yet. I suspect that the documents are perfectly viable, but that those who argue against their use are basing those defensive postures on the life-changing consequences of being found guilty of an NFA-related crime by the ATF.

There is a misconception regarding trusts: and that is that they don't need to be 'registered' somewhere like City Hall or something. They're a legally binding civil document by virtue of their notary-authenticated existence.

At any rate, the short-version of my story was this:
- Went to an office supply store and bought pre-made form for around $40.
- Went to notary and initialed and signed the document along with the notary.
- Submitted the trust with the form 4 and check...
-... with the form 4 specifying that the trust was the owner, and not me.

After that it was the same story as everyone else:
- Class III called back one day and said the silencer was mine to pick up.
- Went and picked up silencer and the returned copy of the Trust.

I hope that answers your question adequately. Again, I wouldn't feel right about putting that into the FAQ, because I feel like it would do two things: it gets closer into giving out legal advice than I feel the FAQ should do - even though there is a "legal" section in the FAQ already. And two, it has the power to diminish the FAQ from being (what I consider to be) 100% trustworthy, down to 96+% since the information I'd be giving out would be more speculative than I'd feel comfortable giving.

However... if some moderators or paralegals or actual lawyer chime in with a fleshed-out, solid answer, I'll certainly include it. I'm not opposed to the information being out and available... just my version of that information being treated as solid, and then having someone act in good faith on bad information and getting into a heap of trouble. I don't think that would come back on me, but it would still cause someone a tremendous amount of hardship.
cyclone72
Silencertalk Goon Squad
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Location: Florida

Re: Silencer FAQ (work-in-progress)

Post by cyclone72 »

Thanks Trooper, believe it or not this helps.
Can Fan
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Re: Silencer FAQ (work-in-progress)

Post by Can Fan »

A very nice and almost complete write-up! First, as a newbie here, hello to everyone! I hope to get to know you all and to make friends here.

The one thing that I didn't see was the corporation route. I already had a LLC as I sell on the internet and to retail stores. No suppressors for sale yet, but I'm looking into it.

Since I had a corporation, I went that route. This method isn't worth developing a corporation, just to get a suppressor. The annual hand out to our fine government is too much to make this method worth it. BUT, if you already have a corporation, it makes sense.

My head LEO is in the family, so that was a possible route. But, he won't always be the Chief of Police. So, I just wanted to add this route to ownership.

Can Fan or Alan works for me!
silent
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Re: Silencer FAQ (work-in-progress)

Post by silent »

I'm new here...
This is an Excellent FAQ. just in that one post a lot of questions were answered that took me a while to learn on my own
much appreciated!
quiettime
Silent But Deadly
Posts: 605
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Location: N FLA

Re: Silencer FAQ (work-in-progress)

Post by quiettime »

silent wrote:I'm new here...
This is an Excellent FAQ. just in that one post a lot of questions were answered that took me a while to learn on my own
much appreciated!
Welcome. The board isn't quite as active as it has been. I think many of us are waiting on multiple stamps to come back and are trying to keep our minds off it! :lol:

It's an exciting time for us as the silencer world has all but completely changed in the last ten years. This year could be the biggest yet with the possibility of the Hearing Protection Act. Enjoy!
silent
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Joined: Wed Dec 28, 2016 9:18 am

Re: Silencer FAQ (work-in-progress)

Post by silent »

quiettime wrote:
silent wrote:I'm new here...
This is an Excellent FAQ. just in that one post a lot of questions were answered that took me a while to learn on my own
much appreciated!
Welcome. The board isn't quite as active as it has been. I think many of us are waiting on multiple stamps to come back and are trying to keep our minds off it! :lol:

It's an exciting time for us as the silencer world has all but completely changed in the last ten years. This year could be the biggest yet with the possibility of the Hearing Protection Act. Enjoy!
thanks!

yeah I know what you mean lol

and i'm new new so any info would actually help :)
tinalloyd
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Contact:

Re: Silencer FAQ (work-in-progress)

Post by tinalloyd »

Thanks for sharing information.
KiraPrince
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Re: Silencer FAQ (work-in-progress)

Post by KiraPrince »

A unique gratitude to Trooper for putting the majority of this data together in one spot. In the event that you have an inquiry that isn't replied, you can post it here and it will be included if fundamental.
https://arynews.tv/en/ is a Pakistani news channel
noeleo
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Re: Silencer FAQ (work-in-progress)

Post by noeleo »

NOOB here.

How do I choose a supressor? :oops: Do I just walk into my LGS and buy what they recommend? :?:

Thanks
noeleo
New Member
Posts: 2
Joined: Sun Oct 13, 2019 5:33 pm

Re: Silencer FAQ (work-in-progress)

Post by noeleo »

noeleo wrote: Mon Oct 14, 2019 6:13 pm NOOB here.

How do I choose a supressor? :oops: Do I just walk into my LGS and buy what they recommend? :?:

Thanks
Forgot to say for .22 cal.
faizanmazhar00
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Re: Silencer FAQ (work-in-progress)

Post by faizanmazhar00 »

TROOPER wrote: Sun Feb 23, 2014 6:52 pm For Starters
FS1 - Is it legal to own a silencer?
FS2 - Why own a silencer?
FS3 - How do I buy a silencer/suppressor?
FS4 - What is the difference between a 'silencer' and a 'suppressor'?
FS5 - Who can buy a silencer?
FS6 - Can I shoot other cartridges calibers through the same silencer? I only want to buy one silencer and use it on multiple guns.

Legal
L1 - How do I handle legal challenges to my suppressor ownership?
L2 - Does purchasing a silencer enable the ATF to search or inspect my residence without a warrant?
L3 - Where do I have to keep my paperwork?
L4 – Where do I have to keep my suppressor?
L5 - Who can use my suppressor?
L6 - Who has the authority to inquire about documentation?
L7 - Can I legally make my own suppressor?
L8 - Can I 'write-off' the $200 tax stamp for tax purposes?
L9 - I have a Top Secret Clearance! Will this shorten the time for my background check?
L10 - I see advertisements or auctions for "solvent traps". What's this about?
L11 - Why do some people use a "Trust"? (This question-and-answer needs updating)
L12 - What is a "Form 1" a "Form 3" and a "Form 4"?

Practical
P1 - How do I clean my suppressor?
P2 - Can I shoot hollow-points through my suppressor?
P3 - Can I shoot .22 LR through my 5.56 suppressor?
P4 - Do I need special ammunition for my silencer?
P5 - Is there any specialty ammunition specifically for silencers?
P6 - Is there any ammunition specifically to avoid in silencers?
P7 - What is shooting "wet"?

General
G1 - What is the quietest possible setup?
G2 - What is subsonic? What is trans-sonic?
G3 - What is a "Nielson Device"?
G4 - Which Firearms require a Nielson Device?
G4.5 - What if I use my silencer with Nielson Device on a fixed barrel?
G5 - What is "First Round Pop"?
G6 - What is "Blowback"?
G7 - Can I put a suppressor on this firearm?
G8 - What is the best suppressor for <insert caliber>?
G9 - My 22 LR rifle and 22 LR pistol are both threaded 1/2 x 28, but the threads are different!
G10 - Why are silencers always so long and skinny? I want one short and wide!
G11 - All things being equal, what is quietest to suppress, 357, 44, or 300 BLK?

For Starters

FS1 - Is it legal to own a silencer?
In some states the answer is "yes", in other states the answer is "no". As of 2/23/2014, the following states/districts prohibits them: California, Delaware, Hawaii, Illinois, Iowa, Massachusetts, Minnesota, New Jersey, New York, Rhode Island, and the District of Columbia. More states allow silencers than prohibit them. Laws are subject to change, so please research your individual state before proceeding.

FS2 - Why own a silencer?
It makes the operation of your weapon quieter. In some instances, the operation can be so thoroughly reduced that hearing protection is no longer necessary. In some states, hunting is permitted with a silencer and there may be advantages to a shot which - while still audible - is less disruptive to the shooter or the environment.
A suppressor will act, in part, like a muzzle-brake by retarding the violent forward expulsion of gas particles, thus reducing felt recoil impulse.
Suppressing your weapon will often make the overall shooting experience more pleasant, especially in prolonged sessions.

FS3 - How do I buy a silencer/suppressor?
There are two ways to start this process. One method is to find the specific make and model that you prefer from a stocking dealer located anywhere in the US (a recommended dealer section is included in the Board Index of this forum). Purchase from that dealer and have them ship the item to a LOCAL, in-state class III dealer who will then walk you through the remainder of the transaction.
A second method is to skip the stocking dealer and go straight to a LOCAL, in-state class III dealer and choose from among what that dealer has in their immediate inventory.
After either of the first two steps, the LOCAL, in-state class III dealer will help you with the paperwork - called a "form 4" - and submitting it, along with a check for $200, to the ATF. After a period of time ranging from several months to a little over a year, the class III dealer will call you and tell you that you may come and retrieve your silencer/suppressor.

FS4 - What is the difference between a 'silencer' and a 'suppressor'?
The words are synonyms from a legal standpoint in that the BATF does not recognize a distinction between their usage. Some people argue that "silencer" is incorrect since the shot is not technically silenced. Others argue that the original Maxim patent is for a "silencer". Outside of the legal realm, the silencer/suppressor community will often refer to a silencer as a "can". In different regions of the world they are also referred to as "muffler" or "moderator", although neither term is commonly used within the United States.

FS5 - Who can buy a silencer?
Assuming your state does not prohibit ownership, then the only other criteria is a non-felon who is 21. Essentially, if you can purchase a handgun in a silencer-friendly state, you may purchase a silencer.

FS6 - Can I shoot other cartridges & calibers through the same silencer? I only want to buy one silencer and use it on multiple guns.
Yes-and-no. Cartridges and pressures vary enough that a simple answer isn't possible. You must always consult the manufacturer's recommendations for your individual silencer. That said, many manufacturers do list the calibers and cartridges which may safely be used with their particular silencers. For example, the AAC Element is listed as being safe for .22 LR, .17HMR and .22Magnum hosts.
One of the challenges of using one silencer for multiple hosts is mounting the silencer since the cartridges - for example 9mm and 45 ACP - may have different threaded mounts. Again, using AAC as an example, and from their website, "For multi-caliber use, pistons are available in the most common 9mm and .40 thread patterns to allow use of the Ti-RANT 45 on hosts in those calibers." However, generally speaking, the best performance will come from using a silencer for the cartridge it was designed for.


Legal
Obligatory disclaimer: the following information is delivered in good faith, however, if it is wrong, it will be you that suffers. Ultimately, it is your responsibility to understand the law and its nuances sufficiently to adhere to state and local regulations.

L1 - How do I handle legal challenges to my suppressor ownership?
If a non-LEO range officer approaches you and demands to see your paperwork, you are not obligated to produce, however, you will most likely be asked to leave. Many silencer users CHOOSE to comply, and merely produce either the paperwork or a copy of the paperwork. Many, many times a silencer user will shoot a session unchallenged even though the range safety officer was aware of the silencer use, but the range officer knew that the items were legally viable within the region and instead did not challenge at all. This is the most common situation.
If a law enforcement officer (LEO) challenges you, the most common response is to produce the requested paperwork. Quite often this will satisfy the situation and it will be completely diffused. However, there have been limited instances where the officers did not fully understand the legalities of his/her region and it took additional time and officer-superior communication to resolve the situation. If this happens, remain calm and understand that you have broken no laws.
A different school of thought is held by some silencer users that the paperwork is a tax document, and therefore out of the jurisdictional purview of the responding police officer. Unfortunately, there are few, few, stories of how such challenges and subsequent noncompliance (legal or otherwise) were resolved.

L2 -Does purchasing a silencer enable the ATF to search or inspect my residence without a warrant?
No. There is a persistent rumor that owning a silencer by default enables the ATF to search your house at their discretion. The ATF are permitted (with provisions) to inspect an FFL's place of business. The rumor probably started due to certain smaller FFLs operating out of their homes' garages, which lead to the myth that anyone with an NFA item such a silencer could also be searched or inspected without a warrant.

L3 - Where do I have to keep my paperwork?
Because the ATF is extremely reluctant to issue new paperwork to replace lost paperwork, it is critical to maintain the originals. Many individuals keep their Form 4 at home either in their gun safe, or a fire safe. Furthermore, the documents will contain sensitive personal information which should be protected (identity theft hazard).
Simultaneously, it is possible and common for the legality of your suppressor/silencer to be challenged in public both by non-LEO range officers or by local police officers themselves. As such, some people keep their paperwork with their suppressor so that they can verify legal ownership as necessary. Others keep photocopies of the information so that the originals remain secure elsewhere.

L4 - Where do I have to keep my suppressor?
It's legally a firearm so the requirements of securing firearms in any local jurisdiction apply with regard to securing NFA devices. In short, to satisfy the ATF, the registered transferee must not facilitate an illegal transfer.
It has been posited before that a cable lock run through the bore of a suppressor by the registered transferee where only the registered transferee has the means to unlock the device might be sufficient to establish "control" of the device even if another has "possession". This would be similar to the NFA being secured in a portable safe (<oxymoron) or the NFA being secured in a safe on premises accessible to non-transferees.

If you live at home alone or everyone in your household is a registered tranferee for the device and there are no local jurisdictions requiring the device to be secured when not in use then you can keep your NFA on the coffee table 24/7.

L5 - Who can use my suppressor?
Short answer, at the range anybody.
Long answer, anyone may use a NFA device in any jurisdiction where the use of the device is legal within the controlling presence of the legal entity registered as the transferee. The key element here is the registered transferee must maintain control of the of the device so as not to constitute an illegal transfer. This does not necessarily mean the registered transferee must maintain line of sight or a physical connection with either the NFA or the "guest" user. It has been posited that a non-transferee can reasonably expect to use a NFA on 500 acres of private property where the registered transferee is present but that is not the same as a non-transferee using a NFA on 500 acres of public land where the registered transferee is "around somewhere".

L6 - Who has the authority to inquire about documentation?
The three most common entities who will inquire are the non-LEO, non-employee, fellow customer/shooter.... the acting representative of the property at which you are using the silencer, specifically a Range Safety Officer... and the Law Enforcement Officer (LEO). How you handle a non-employee, non-LEO is your discretion. How you handle the employee who is non-LEO is also your discretion, although this entity does have the authority to order you off of the premises. The third entity has still greater authority, and since it is generally understood that an UNREGISTERED silencer/suppressor is illegal, proving that yours IS registered may be to your advantage. It should be noted that many - probably MOST - suppressor owners do comply with LEO paperwork requests.
Please do note that the list above is the common list, but NOT a comprehensive list, and additional agents or entities may inquire into your documentation.

L7 - Can I legally make my own suppressor?
Yes. The proper paperwork to submit is a "Form 1" and requires ATF clearance to proceed. A more in-depth discussion and "how-to" can be found here.

L8 - Can I write-off the $200 tax stamp for tax purposes?
No.

L9 - I have a Top Secret Clearance! Will this shorten the time for my background check?
No. A number of members on this board have claimed to hold security clearances and have indicated that their approval wait times are no different than anyone else. It is possible that some people claim to have a security clearance on the internet without actually having one. However, in the "wait-tracking-thread", while some times are shorter than others, none seem to be out of step; IE, those who start the process at the same time with the same approver, tend to end at about the same time.

L10 - I see advertisements or auctions for "solvent traps". What's this about?
Unfortunately, the moniker "solvent trap" may mean a few things, but if you're reading about it here on this forum, that means you think it is a silencer. Well, it is a silencer. In all likelihood, it's an unregistered silencer, and you can expect life-changing legal repercussions if you purchase it off of EBay or Craig's List or Soldier-of-Fortune or wherever you saw it. If you live in the US, avoid it.

Does it work? It may or may not work, but intent is what the government prosecutor will be looking for, and to add insult to injury, you may end up in prison for a silencer that doesn't work well.

L11 - Why do some people use a "Trust"?
There are two dominant reasons to use a Trust. The first and primary reason is that the individual lives in an area where the local law enforcement officer (LEO) is not supporting of NFA items such as silencers, transferable machine guns, or short-barreled rifles (SBR). In which case, by using a Trust, the individual is able to avoid having to have their LEO sign-off on the matter.

Originally, the LEO sign-off was to prevent individuals who are under investigation for a crime from acquiring an NFA object. A NICS background check won't uncover if a person is under investigation, only actual records. Since a Trust cannot be under investigation for committing a crime, it follows that a Trust will not need an LEO sign-off or finger-prints.

The secondary reason for using a Trust is that the Trust-holder can assign "trustees" who may then have more unfettered access to the items on the Trust. Although this is a distant motivation for establishing a Trust.

Note: if you have a Trust set up, and you eventually have an SBR made, then the name of the Trust will be what is engraved on the SBR. It is therefore in your interest to avoid overly long Trust names, while simultaneously embracing awesome names, IE: "Zombie-Megatron-Space-Ninja-Pirate-Trust".

L12 - What is a "Form 1" a "Form 3" and a "Form 4"?
Form 1 -- This form is to allow the end-user the ability to manufacturer an NFA item such as a silencer, an SBR (short-barreled rifle), or an SBS (short-barreled shotgun).

Form 3 -- This form allows an FFL/SOT to transfer an NFA item, such as a silencer, to another FFL/SOT. Most people in the NFA world will never have any use for this form.

Form 4 -- This form allows for the transfer of an NFA item, such as a silencer, from an FFL/SOT - usually just called a "Dealer" or "Class III" - to an end-user. This is the most common method of acquiring a silencer: you fill out a form 4 and send it off to the ATF with a check in order to transfer the silencer from the dealer to you.



Practical

P1 - How do I clean my suppressor?
Many centerfire rifle suppressors do not need to be cleaned due to the high pressure nature of the cartridge. This is often true for centerfire pistol silencers as well. However, rimfire suppressors - regardless of pistol or rifle host - WILL become excessively clogged and dirty over time, and as such, will suffer gradual loss of suppression, although it should be noted that this is a long-term process. As a result, conventional wisdom recommends the purchase only of "user-serviceable" rimfire silencers since a "sealed can" will have a finite number of shots built in to it until the manufacturer, or competent machinist, adequately services the suppressor.
It should be noted that cleaning for "user-serviceable" cans is material specific if the user intends to use chemicals. However, for all "user-serviceable" silencers, a copper wire brush is acceptable just as one would clean a fouled barrel.

P2 - Can I shoot hollow-points through my suppressor?
Yes.

P3 - Can I shoot .22 LR through my 5.56 suppressor?
It is very strongly recommended that you not do this. While it is true that any 5.56 silencer can safely handle the pressures associated with a .22 LR, the problem is that .22 LR is very dirty, and leaves a lot of carbon and lead residue inside of a silencer. After enough of this, the internal volume of the silencer is reduced to such a point that when the user switches back to the higher-powered 5.56 NATO, the pressure spikes to unsafe levels and may result in a catastrophic failure.
Please note that this procedure is safe if the manufacturer of that particular silencer states that it is.

P4 - Do I need special ammunition for my silencer?
Ammunition that does not exceed the speed of sound will be the quietest. This ammunition is referred to as "subsonic". Some calibers are subsonic in almost all instances, such a 38, or 380. Other calibers are sometimes subsonic, and sometimes supersonic, depending on loading. Specifically 9mm, 40 S&W, and 45 ACP. For all three, the heaviest factory loadings will typically be subsonic out of pistol-length barrels. But all three may also be supersonic if used in their lightest factory weights, and therefore not as quiet when shot through a silencer.
However, it is not necessary to use specialty ammunition -- merely a caliber determined safe by the silencer manufacturer, and within SAAMI limits (anything factory). Bottom line: if you have a 9mm silencer, you can shoot 9mm through it whether it's supersonic or not. Same for 45 ACP and any other caliber.

P5 - Is there any specialty ammunition specifically for silencers?
There are three basic types of specialty ammunition.
1 - The first type is merely marked as “suppressor ammunition” by virtue of the fact that it is subsonic in most hosts. An example is certain 9mm marked as “silencer ammunition” when in reality it has no extra manufacturing to differentiate it from ordinary 147 gr 9mm – which will always be subsonic out of a standard sized handgun. It is true that it is good for use on a silencer, but its results will not be distinguishable from ordinary 147 gr without any ‘silencer’ markings on the box.

2 - The second type of specialty ammunition is one in a common caliber that is somehow different from ordinary loadings, although the chambering remains the same. Aguilla SSS 22 LR is a 60 gr rimfire which is significantly different from other 22 in that ordinary 22 LR will typically top out at a weight of 40 gr. GemTech also makes specific 22 LR ammunition which has both a reduced powder charge, but also a heavier than normal 42 gr weight. Fiiochi, as well as IMI, both make a 158 gr 9mm. These are different specifically because their specifications fall outside of the normal range for their respective caliber.

3 - The third type of ammunition is a cartridge which was made specifically for silencer use as opposed to being incidentally good in the way that 147 gr 9mm is. The “Whisper” line of cartridges, and the 300 Blackout (300 BLK) are specifically made to provide top-tier silencer performance.

P6 - Is there any ammunition specifically to avoid in silencers?
Yes: "WinClean" ammunition has been reported to have a sort of sand-blasting effect on the interior of silencers, and may result in a markedly shorter lifespan of the unit. Also, unjacketed lead bullets may leave deposits inside of silencers that may shorten the life of the unit. It is for this reason that many of the top-of-the-line rimfire suppressors are take-apart / user-serviceable specifically to counter this leading effect. In centerfire silencers, there have been mixed reports and speculation advising against this activity.

P7 - What is shooting "wet"?
Shooting "wet" means that the user has put a small amount of fluid - usually water, but sometimes 'pulling gel' or white lithium grease - into the silencer and agitated the unit in order to make as much of the surfaces wet as possible. Due to the ideal gas law - PV=nRT - a decrease in temperature due to the heat of vaporization will necessarily lead to a reduction in pressure on the other side of the equation. This can make a notable difference in sound reduction. You must consult your manufacturer to determine if this is a safe practice for your particular silencer, since the addition of a non-compressible liquid necessarily reduces the amount of internal volume, which could lead to unsafe pressure spikes with certain cartridges. However, it is generally recognized as a safe practice with rimfire and pistol-caliber silencers, and always with very small amounts of fluid.


General

G1 - What is the quietest possible setup?
It is generally agreed upon that a bolt-action rifle chambered in 22 LR, shooting subsonic ammunition, through an integral silencer (a silencer which is built into the firearm and is not removable), wet.... will be the current quietest setup.

G2 - What is subsonic? What is trans-sonic?
Subsonic means "less than the speed of sound". In feet-per-second, this works out to around ~1,000 FPS and up to ~1,100 FPS. The higher number is generally the more accurate number, but temperature, humidity, and height above sea level all come in to play. It is generally regarded that within the continental US, if the bullet is traveling at 1,000 FPS or less, it will be subsonic.
Trans-sonic refers to a particular phenomenon whereby even though the bullet itself is traveling at less than the speed of sound, the air itself goes supersonic as it moves around the bullet. People who are unaware of this phenomenon may be confused if they are using a chronograph, but are still hearing the tell-tale sounds of super-sonic crack.

G3 - What is a "Nielson Device" or "booster"?
A "Nielson Device" - or "booster", which is the exact same thing - is a type of coupling device which helps to ensure reliable cycling for silencers mounted on Browning-style actions - also called "tilt-barrel" actions. In a pistol such as a GLOCK, if the user locks the slide to the rear, it will be clear that the barrel is tilted slightly upward, and is no longer parallel with the frame. Since the barrel tilts up during any normal cycle from a gunshot, the added weight of a silencer on the barrel might retard the ability of the barrel to tilt upward, thus causing FTFs and possible FTEs. A Nielson Device enables the silencer to quickly de-couple so that the barrel can tilt normally momentarily without also lifting the weight of the silencer.

G4 - Which firearms require a Nielson Device?
Essentially any firearm that does not have a fixed barrel can benefit from a Nielson Device. Therefore rifles are best without a Nielson Device. Certain fixed-barrel handguns are best without a Nielson Device. Furthermore, many "micro" or "compact" suppressors do not require a Nielson Device since their weight and length are reduced enough that the extra weight placed on the barrel is insufficient to adversely affect reliability.

G4.5 - What if I use my silencer with Nielson Device on a fixed barrel?
The typical situation where this would occur is if, for example, you take a 9mm silencer with booster off of a GLOCK and then immediately screw it on to a 9mm rifle without removing the booster. It has been suggested that this is bad practice since the silencer will still have the ability to move and shift with shots, and may cause a 'jackhammer' type of effect on the threading as a result. It is for this reason that many booster'ed silencers also have the option of utilizing a 'fixed spacer' specifically to avoid this wear-and-tear. Using a booster'ed silencer on a fixed barrel is considered unnecessarily risky to the threads.

G5 - What is "First Round Pop"?
First-Round-Pop, or FRP, is the louder-than-normal (for a suppressed shot) FIRST shot. This is considered to occur due to ambient Oxygen being combusted inside of the first chamber of the suppressor by unburned powder being ejected from the gun muzzle. The FRP is louder than the normal suppressed shot, but only subtly so, and it will not be confused with an unsuppressed shot. Certain designs or cans tend to have louder FRP than others -- see following question.

G6 - What is "blowback"?
Blowback, as it pertains to silencers/suppressors, refers to the phenomenon of increased soot, residue, or just gas being ejected from the rear of the gun - usually from the ejection port. This occurs because the muzzle of the gun will experience slightly increased levels of pressure when suppressed, and so the gas - which seeks the lowest pressure area - will partially vent through the rear of a gun. Bolt-actions are essentially immune from this phenomenon, while blow-back operated pistols (most 380s and many 22 pistols) will have the greatest increase in "blowback". Other operating systems such those used by ARs will have an increase, though not as severely as a blow-back operated firearm.
"Blowback" and "First Round Pop" are considered by some to be connected in that a silencer with a relatively large first chamber (blast chamber) will tend to have the most FRP, but a decreased Blowback.... and vice-versa.

G7 - Can I put a suppressor on this firearm?
Yes. Any gun can have a suppressor - any gun can be suppressed. However, certain firearms, such a shotgun, require such a specific and cumbersome type of suppressor that it becomes impractical, still not quiet enough, and is generally considered a poor idea although still technically feasible. Certain other types of firearms require additional care or modifications to accept a suppressor safely. For example, an AK-pattern rifle sometimes has issues (dependent on the manufacturer) with having a bore that is concentric with the barrel; therefore, if a silencer is attached, the bullet may strike or glance off a portion of the silencer as it exits. Other firearms, such as a Desert Eagle, have other issues such as altering the back pressure on a system that relies on siphoning off gas within a certain window of tolerances. Still other firearms simply do not suppress well for various other reasons.
The take-away on this question is that any firearm can be suppressed, although not all receive equal benefit from a suppressor. Please ask about your particular firearm, and you will receive viable feedback.

G8 - What is the best suppressor for <insert caliber>?
No make or model is given for the sake of this FAQ since the answer changes as newer models come to the market. However, this question is asked often enough that components of this question shall be addressed. This question is challenging based on your criteria; meaning that if absolute suppression is your primary objective, then there might be a specific answer. However, if cost, or weight, or materials, or appearance are your primary concern, then there are different "best options" for each of those respectively. No one unit is the best in every category... or no other make and model would ever be sold. When asking this question in an open forum to solicit responses on the current "best", it is important that the person asking understand that there are many metrics to rate a silencer, to include (in no particular order): cost, availability, weight, length, level-of-suppression, materials, fit-and-finish, appearance, ease-of-cleaning (when applicable), customer service, as well as specific answers related to your particular intended host, as certain suppressors have different characteristics related to FRP, blowback, full-auto capabilities, and level of suppression for pistol versus rifle. When asking this question, the more information you are able to share regarding the characteristics that are important to you, the better advice you will receive.

G9 - My 22 LR rifle and 22 LR pistol are both threaded 1/2 x 28, but the threads are different!
Many rifles with threaded barrels of 1/2 x 28 are cut so that the length between the muzzle and the 'shoulder' are longer than a similar threaded pattern for most pistols that are also threaded 1/2 x 28. In order to ensure the safest performance from your silencer, it should be screwed on until it butts up against the 'shoulder' of the threads, which should keep the silencer relatively stiffly attached to the barrel, as well as parallel to the bore. A silencer that is incompletely screwed on may have enough 'wobble' in it to risk the bullet striking or touching some portion of the silencer as it exits. In order to appropriately screw some silencers onto the longer version of 1/2 x 28 threads commonly seen on ARs as well as other rifles, the user should acquire a "Spacer" from a reputable silencer company. These items are not legally controlled, and so can be purchased with minimal wait time and without legal procedure. A spacer will effectively move the 'shoulder' forward, and still allow the silencer to be screwed on to the appropriate level of tightness, thus ensuring a relative stiffness of connection between silencer and barrel.
It has been noted that simply using a washer obtained from a hardware store may produce poor results since these mass-produced washers will lack the necessary tolerances to ensure -- once tightened -- that the bore of the suppressor remains parallel to the bore of the barrel.

G10 - Why are silencers always so long and skinny? I want one short and wide!
There are three key factors which influence the efficacy of a silencer: the internal volume of the silencer, the number of baffles, and the design of the individual baffles.
According to an industry professional, "The main reason you don't see a ton of cans like this is because in terms of performance, diameter (volume) is no replacement for length and additional baffles. The 'task' of the can is to strip away gas from the bore, you need baffles along the path of the gas to accomplish this. You end up with a can that is heavier for a given length, and not as efficient as a slightly longer one. Volume inside the can plays a part (why we don't see 1" diameter rifle cans), but it's secondary to length."

G11 - All things being equal, what is quietest to suppress, 357, 44, or 300 BLK?
For this question, assume subsonic loadings are used, and in equal length barrels. In which case, the only difference would be the bore-hole of the silencer. Therefore, the caliber that required the least amount of bore diameter through the silencer would be the quietest. For best suppression, the baffles must strip away gas as described in question G10 - but this process is hindered by a large hole through the middle of the silencer which the bullet must travel through which the gas may also travel through. It is for this reason that - all things being equal - smaller diameter calibers suppress better than larger diameter calibers.
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jktranslate
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Re: Silencer FAQ (work-in-progress)

Post by jktranslate »

Silencer smiting discussion was a decent asset for Structure 1 forms and most dynamic gathering on the site. Never joined yet enjoyed perusing. Site is still up however no posts since late Walk. Never was a high volume site yet there was a consistent stream of posts.
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mr fixit
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Re: Silencer FAQ (work-in-progress)

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emmajames
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Re: Silencer FAQ (work-in-progress)

Post by emmajames »

your L7 answer :
If you are considering making your own suppressor, it is strongly recommended to consult with legal professionals or contact the ATF for guidance to ensure that you comply with all relevant laws and regulations. Violating firearm laws can result in serious legal consequences.
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