Barrel Length Supressor

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WinMag
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Barrel Length Supressor

Post by WinMag »

Hello everyone! I apologize if this has been covered, as although I could not find anything pertaining to it, its such a simple idea that Im sure it has to have been posted. I would like to try my hand at building a form-1 suppressor, but the only tools I have access to are a lathe and drill press. I had the idea to simply get a long thin-wall SS-304 pipe and instead of building a normal suppressor, I would simply thread the endcap, and xtend the pipe back over the barrel towards the receiver. I would then port the barrel approximately 6-8" behind the muzzle, the idea being that the bullet would act as an efficient baffle directing the gasses into the "barrel shroud." The tricky part would be the rear seal against the barrel, but I have a few various ideas for that....Links or reasons why this wont work? (We recently legalized suppressors for hunting here in TX, and I want to build a dedicated .243 rifle for deer/hogs)
Scared_of_zombies
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Re: Barrel Length Supressor

Post by Scared_of_zombies »

WinMag wrote:Hello everyone! I apologize if this has been covered, as although I could not find anything pertaining to it, its such a simple idea that Im sure it has to have been posted. I would like to try my hand at building a form-1 suppressor, but the only tools I have access to are a lathe and drill press. I had the idea to simply get a long thin-wall SS-304 pipe and instead of building a normal suppressor, I would simply thread the endcap, and xtend the pipe back over the barrel towards the receiver. I would then port the barrel approximately 6-8" behind the muzzle, the idea being that the bullet would act as an efficient baffle directing the gasses into the "barrel shroud." The tricky part would be the rear seal against the barrel, but I have a few various ideas for that....Links or reasons why this wont work? (We recently legalized suppressors for hunting here in TX, and I want to build a dedicated .243 rifle for deer/hogs)
It'll work to an extent. Basically it's just an expansion chamber. Only having a place for gas to expand, rather than "working it" will lead to less suppression for a given volume. Either you get poor results or you have to have an incredibly large tube. If you have a lathe then please make full use of it. 60 degree cones and spacers will work well for that round.
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Capt. Link.
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Re: Barrel Length Supressor

Post by Capt. Link. »

If you are new to suppressors keep in mind that the supersonic crack a .243 makes will not be reduced by a suppressor and is just as loud as the muzzle blast.With a lathe you can make all you need cones work fine.
The only reason after 243 years the government now wants to disarm you is they intend to do something you would shoot them for!
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895
one-eyed Jack
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Re: Barrel Length Supressor

Post by one-eyed Jack »

Rememer that you need to let the gasses expand AND cool. So, you need something between the barrel od and the tube id. You could thread the end of the barrel, make the rear end cap a drive fit onto the barrel and use a nut to drive the front end cap and tube against the rear end cap. However, on a form 1, they frown on experimenting, and you would have to play with hole sizes, quantities of holes and types of packing. Also, deburring the holes on the barrel id is a bitch. Ask me how I know. Jack.
WinMag
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Re: Barrel Length Supressor

Post by WinMag »

Thanks for the responses guys. I think in going to start my experimenting on a .22. Once the form comes thru if course. With only a .22 and such a large volume to work with I think I will just machine the rear end cap to the diameter of the barrel and use 2-3 o rings to seal the rear. I'll taper it to mach the barrel so as I thread the tube on it will be a nice press fit with the barrel. It would be interesting to see if I could port it enough so that normal .22 rounds would go sub sonic before they left the barrel. Also I plan on making a "normal" baffle supressor later on down the road, I just want to start with what I think to be the easiest method. Additionally I like the idea of not adding any additional length to the gun.
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Capt. Link.
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Re: Barrel Length Supressor

Post by Capt. Link. »

WinMag wrote:Thanks for the responses guys. I think in going to start my experimenting on a .22. Once the form comes thru if course. With only a .22 and such a large volume to work with I think I will just machine the rear end cap to the diameter of the barrel and use 2-3 o rings to seal the rear. I'll taper it to mach the barrel so as I thread the tube on it will be a nice press fit with the barrel. It would be interesting to see if I could port it enough so that normal .22 rounds would go sub sonic before they left the barrel. Also I plan on making a "normal" baffle supressor later on down the road, I just want to start with what I think to be the easiest method. Additionally I like the idea of not adding any additional length to the gun.
I think you are selling your self short in building a 1940's suppressor in 2012.If you can make basic parts on your lathe you can build a simple effective suppressor that will not add to your rifles length or take up to much time.The end caps are the hardest part to make and many simple baffles not seen on these pages can be used with great success.
The only reason after 243 years the government now wants to disarm you is they intend to do something you would shoot them for!
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895
WinMag
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Re: Barrel Length Supressor

Post by WinMag »

Capt. Link. wrote: I think you are selling your self short in building a 1940's suppressor in 2012.If you can make basic parts on your lathe you can build a simple effective suppressor that will not add to your rifles length or take up to much time.The end caps are the hardest part to make and many simple baffles not seen on these pages can be used with great success.
Not sure what you mean about not adding length or baffles not seen on these pages. How can you have a baffle design that doesnt add to the length? Do you have any links to the baffles youre talking about? If its not going to be efficient, and by the responses Im getting Im guessing its not, ill go back to the drawing board and try out a "normal" can first. Thats why Im here! Thanks
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Capt. Link.
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Re: Barrel Length Supressor

Post by Capt. Link. »

WinMag wrote:
Capt. Link. wrote: I think you are selling your self short in building a 1940's suppressor in 2012.If you can make basic parts on your lathe you can build a simple effective suppressor that will not add to your rifles length or take up to much time.The end caps are the hardest part to make and many simple baffles not seen on these pages can be used with great success.
Not sure what you mean about not adding length or baffles not seen on these pages. How can you have a baffle design that doesnt add to the length? Do you have any links to the baffles youre talking about? If its not going to be efficient, and by the responses Im getting Im guessing its not, ill go back to the drawing board and try out a "normal" can first. Thats why Im here! Thanks

You can build a integral suppressor that will not make your rifle any longer.Your barrel will be shorter but the OAL is the same or shorter unless you wish to add a tax stamp.10-22s are popular to build and a integral with a 16" tube is 2" shorter than the standard carbine.Suppressors need not be complicated to work well.A mono-core of simple design will work much better than the design you are contemplating and may be less work.Other rifles work just as well.
The last commercial rifle built in that way was by Ciner it sucked.I'm just trying to encourage you to building a better suppressor.I can help you and others can also.
The only reason after 243 years the government now wants to disarm you is they intend to do something you would shoot them for!
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895
ranb
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Re: Barrel Length Supressor

Post by ranb »

Perhaps a simple drawing of what you want would help explain things? I only have a lathe, drill press, grinder and welder to work with but have no peoblem making a decent silencer. I tried porting a rifle barrel with a drill press and it failed terribly as I get copper shavings in the can now. Porting only degrades ammo performance in my opinion. Load the ammo for the speed you need. The lower powder charge will aid in suppression.

If you are thinking of only having the silencer tube around the ported barrel and not extending past the muzzle, I think you will not get much in the way of noise reduction. You will need an expansion area filled with baffles past the muzzle to get any reasonable suppression.

Ranb
SilencerTalk was a place I could disccuss making registered silencers without being told I was a criminal. That is no longer true. http://www.silencertalk.com/forum/viewtopic.php?f=132&t=99273
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LavaRed
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Re: Barrel Length Supressor

Post by LavaRed »

With the tools you own you can make pretty much anything required for a full quality suppressor.

In my humble opinion, turn down the current barrel slightly where it meets the receiver, machine a groove into it, secure an O-ring there. Then take a solid bar of steel and machine a monocore; there's several good designs on here. Said monocore should flare out towards the muzzle sothat it matches the tube OD. Right behind the flare, turn down to ID and machine another groove for a second O ring. 8 inches of monocore should be sufficient.

Now, you can either cut off 8 inches of barrel or add 8 inches to it. Turn off the sight and bases, if there are any, thread the barrel end and monocore, and voila! you have created a fully effective barrel- length suppressor with a tensioned barrel and tube (best for accuracy), a secure gas seal at both ends, and top-level performance, if you go with a suitable monocore design.

You can use a reverse-baffle in the blast chamber to redirect some gases back into the reflex chamber for additional suppression. You could also use artificial-environment technology by partially filling up the reflex chamber with material that will retain moisture, and wetting it so that the air inside the suppressor will be a nice water-vapor/air mixture, a far more efficient working medium from a thermodynamical viewpoint. And it shouldn't make your pressure spike that much since it's not being converted to vapor directly in the suppressor.

Really, this has the potential to be a top of the line system if you are willing to favour performance over speed.
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Capt. Link.
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Re: Barrel Length Supressor

Post by Capt. Link. »

This is what makes this group the best, you ask and your cup runneth over.I think if you tell us what rifle you wish to suppress and what length you desire you can make a rifle that is quiet accurate and safe.
The only reason after 243 years the government now wants to disarm you is they intend to do something you would shoot them for!
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895
WinMag
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Re: Barrel Length Supressor

Post by WinMag »

Excellent info, thanks a lot. I would like to suppress two rifles, a Ruger 10/22 and a Rem 700 in .308 (18" hvy contour barrel). Prob not gonna worry about the .243 anymore, the .308 will be better for subsonic rounds. Just yesterday I was about to pull the trigger on a SDN-6...I just couldnt stop thinking of the amount of material Id be able to buy for $1k. Ill prob wish I just bought it in the end, never been someone who buys something I think I can make is the problem.
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Re: Barrel Length Supressor

Post by mooface »

I owned a suppressor just like you are describing in the early 80's

The AR7 (then made by charter arms, now by Henry) has a thin steel liner in a tapered plastic shroud.

A suppressor was sold that duplicated the contour of the outer shroud with a tapered aluminum tube surrounding a ported barrel. There was maybe 1/4 to 3/8 extra annular space which you were supposed to pack with steel wool (this was exceedingly difficult in practice) It was ported heavily enough to make most 22LR subsonic, but some of this may have been due to the extensive bore burring slowing the round mechanically. The AR7's already poor accuracy was significantly reduced.

It was neat in that you could only tell it was a suppressor by looking down the bore. As I recall they also were made for the 10/22 and a buddy of mine had a very similar unit on a tube fed marlin model 60.

It was reasonably effective by 1980's standards which is to say quite poor compared to modern units.

So yes, what you are proposing can and has been done but in the end may be more difficult and less effective than other designs.
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Re: Barrel Length Supressor

Post by Historian »

Capt. Link. wrote:This is what makes this group the best, you ask and your cup runneth over.I think if you tell us what rifle you wish to suppress and what length you desire you can make a rifle that is quiet accurate and safe.
Speaking about cups that runneth over, thank you Good Captain for your inspiring icon each time
you post.
Now as for our friend LavaRed's icon ...how legal is that young lady, really, you devil? :)

Now back to serious topics.
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Re: Barrel Length Supressor

Post by redtazdog »

Yes integrals take more time to make but if you have several other muzzle cans and want to go integral
to make the OAL short and quiet on a host then hell why not.
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They work so well that I have made several other integrals
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mooface
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Re: Barrel Length Supressor

Post by mooface »

I myself greatly prefer integrals

To me there is something to having a dedicated suppressor/host combo.

I guess as a young'n I was taken by the de lisle.
WinMag
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Re: Barrel Length Supressor

Post by WinMag »

Thanks Redtazdog, those pictures are awesome. Still trying to decide what to do...thinking of a combo with only 2 or 3 baffles in front of muzzle with a larger blast chamber extending towards receiver. So much studying to do.
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Re: Barrel Length Supressor

Post by redtazdog »

WinMag wrote:Thanks Redtazdog, those pictures are awesome. Still trying to decide what to do...thinking of a combo with only 2 or 3 baffles in front of muzzle with a larger blast chamber extending towards receiver. So much studying to do.
On the AR 223/556 integral the large reflex chamber reduced damn near all blow back crap in the face compared to
several 223 muzzle cans I use.
More baffles in front of the barrel will reduce sound unless you wrap a ported barrel with baffles like I did but then
that barrel is only 11" and when ported OAL 16" and with the integral tube on the OAL is 18"
I ended up with 7 baffles in front of the 11" of unported part of the barrel.
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Re: Barrel Length Supressor

Post by WinMag »

Red, Could you please elaborate on the rear can-to-barrel fit, like in the third picture from the bottom? This AR setup is amazing, Im really impressed. Did you have to get an adjustable gas block or how did you overcome cycling issues?

Edit: found your build thread.
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Re: Barrel Length Supressor

Post by Grounded »

Sorry to dig up an oldie/goodie but can anyone ID this stock....


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Re: Barrel Length Supressor

Post by Grounded »

Never mind, Nordic components CRS... and its discontinued :(
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Re: Barrel Length Supressor

Post by bitfi3nd »

I ordered one of these awhile ago, closest you'll get to that and it has a custom carrier for the short buffer tube. If you wanted it for a .22, nevermind.
If not, it's the closest thing to a Honey Badger stock on the market right now.

http://www.theammosource.com/index.php? ... 28ed1ae7f1
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Re: Barrel Length Supressor

Post by Grounded »

bitfi3nd wrote:I ordered one of these awhile ago, closest you'll get to that and it has a custom carrier for the short buffer tube. If you wanted it for a .22, nevermind.
If not, it's the closest thing to a Honey Badger stock on the market right now.

http://www.theammosource.com/index.php? ... 28ed1ae7f1

Thanks for the info... I saw that and its pretty steep.

I may retrofit an airsoft m231 stock since its only a 22 plinker.

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Re: Barrel Length Supressor

Post by pmercer »

I made up a replacement barrel nut for my at integral. You can see the thread here.
viewtopic.php?f=10&t=19456
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Re: Barrel Length Supressor

Post by whiterussian1974 »

This is actually an excellent concept. The advice that other posters have given, also excellent.
Mag-na-port ports rifle barrels. If you can limit the ports to grooves instead of lands, then you shouldn't have the copper shavings problem. If this DOES occur, then you will need to bore the rifling out for those 6 inches so that the bullet needn't contact the barrel beyond the ports. This section will essentially become an elongated target crown.
Some air will bleed past the bullet in this case, but this actually benefits in suppression. By lengthening the gas discharge timespan and slowly increasing the outflow pressure, the air volume at the muzzle will suffer less sudden disturbance. It will push the air away more than compressing it.
Report R-1896 clarifies these points. The porting admits high pressure gas into the accumulator resivoir, but it only slowly readmits it back into the barrel once that section normalizes.
I thought up a similar plan, but using a muzzlebrake to force gasses backward along the barrel. Your system would seem to work even better.
See the Bell Labs design on page 104 of Report R-1896 for a picture of your concept on a M3 .45 Submachinegun. The results and description follow. The Precursor wave is 115 dB and Blast wave is 130 dB. This system brings the psi from a peak of 20 kpsi down to 200 psi at the muzzle.
They used 48 .25" holes along the barrel. Fewer holes @ .125" diameter would work better with a high pressure round.
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