Suppressor Build Question

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R1Enhanced
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Suppressor Build Question

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I am currently waiting on my Form 1 tax stamp approval before I purchase any materials for my build, I know I can legally but don't want any reason for rejection. I want to build one mainly for 300 BO pistol shooting subs, but I also want it for 300 BO rifle to hog hunt with. I have read soooooo much until I think I am more confused than when I started. First off I'm not really concerned all that much with weight vs durability of materials. I plan on making a stacked M clipped baffle and have a design that I like. Also I have the ability and all machinery that is needed, minus an annealing oven. Question is what is more durable for both subs and supers, SS or Titanium for those pressures of supers? Also do you really need to tig the baffles to the sleeve and what does that help? Thanks for any help.
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Capt. Link.
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Re: Suppressor Build Question

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R1Enhanced wrote: Mon Feb 01, 2021 9:32 pm I am currently waiting on my Form 1 tax stamp approval before I purchase any materials for my build, I know I can legally but don't want any reason for rejection. I want to build one mainly for 300 BO pistol shooting subs, but I also want it for 300 BO rifle to hog hunt with. I have read soooooo much until I think I am more confused than when I started. First off I'm not really concerned all that much with weight vs durability of materials. I plan on making a stacked M clipped baffle and have a design that I like. Also I have the ability and all machinery that is needed, minus an annealing oven. Question is what is more durable for both subs and supers, SS or Titanium for those pressures of supers? Also do you really need to tig the baffles to the sleeve and what does that help? Thanks for any help.
First chill most of us don't eat first time posters and we will try to set you straight.
You need to set the baffle type and spacing for the favored projectile velocity with the strength for the hi-pressure loads.
You don't mention rapid fire so material selection is easy. I like 17-4 for the baffles and titanium for the rest. This will be plenty strong and keep the weight down. If titanium is to costly 316 is a fine substitute.
Nothing wrong with M baffles but cones and spacers may be easier. A dozen close spaced 60* cones will work fine. You can build a hybrid mixing cones with K baffles. This design work well for sub's & supers. M-M-M-K-K-K-K
I don't see any reason for welding unless you want to.

Best-CL
The only reason after 243 years the government now wants to disarm you is they intend to do something you would shoot them for!
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Re: Suppressor Build Question

Post by R1Enhanced »

Capt, I really appreciate your response. No there won't be any rapid fire maybe a few 3 rounders but no mag dumps. Titanium and or 17-4 cost is no problem I just was wanting to build a suppressor that lasts that I build whatever material. I'm mainly wanting to just run my 300 BO pistol with the suppressor, and I have reloaded quite a few sub rounds just for testing once I finally get the go ahead. Am I mistaken that 17-4 requires annealing for the best reliability, maybe I'm wrong. I just noticed most Form 1 builds state to use a SS blast chamber so that just made me wonder about building the entire suppressor out SS and I understand 17-4 is. I honestly did not want to tig it if no need to. So if I build the entire suppressor out of 17-4 would that be the build that can take subs out of a pistol and a rifle 300 BO with supers? Again not really worried about weight for this one. It is crazy that a Form 1 takes so much less time for approval than buying one from a dealer. I guess Form 4 is the kicker. Just so you know I'm not a new kid, been shooting and reloading FOREVER, just new to the suppressor builds. Again thank you so much for your response! Have a great night
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Re: Suppressor Build Question

Post by whiterussian1974 »

The main benefit of Ti is light weight. I like having a Ti tube, and the rest SS. 17-4 spacer to line the blast chamber and the blast baffle would be great. You could go to 316-SS for the remainder of the baffles and spacers if you wish, as most of the heat/pressure will be contained/delayed by the blast chamber.
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Re: Suppressor Build Question

Post by R1Enhanced »

Thanks white Russian I appreciate the response, funny I was just looking at material and checked back on here for any responses. I am thinking of going with Ti tube and 17-4 cups and spacers. Question do you have to anneal the 17-4 to ensure its yield strength or is it ok as is in a suppressor build? Also the Ti which grade? I know that Ti6 only comes in bar stock to be bored and that can be done if needed, or is there a close 2nd that would work fine that is already sold in tubing? Again thanks for your response.
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Re: Suppressor Build Question

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Ti alloy tubing 3AL-2.5V .065" ------28vtpi w/ high % of thread engagement. 17-4 ph900 (not annealed) bar stock typical building material.
Stainless and titanium benefits being resistant to the residue left by nitro cellulose powder. They are also lower upkeep without a finish to care for or wear off. You can mix and match alloys for the most part.

I see no reason to line a titanium blast chamber but you may for ease of construction. A double butted blast chamber spacer/liner = light strong
Image

-CL
The only reason after 243 years the government now wants to disarm you is they intend to do something you would shoot them for!
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Re: Suppressor Build Question

Post by R1Enhanced »

Capt, once again thanks for that information, and detailed material list. That is the materials I will use once I get my stamp in. If i can bother you once more, the double butted blast chamber example that is shown, would that be bored in the Ti tube and if so any close dimensions that I could use? Meaning thickness of the butted part and maybe a little thicker dimension in between to add strength to the blast chamber. Or is that a sleeve inserted into a straight bore Ti tube, with those said dimensions? Thanks again Capt.
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Re: Suppressor Build Question

Post by whiterussian1974 »

The butting refers to welding the SS liner into place within the Ti tube. This prevents uneven heating and pressure upon the Ti tube. (Prevents leakage around the ends of the spacer.) It isn't required, but it strengthen the chamber and prevents uneven stressing. (Like Capt said, the liner really isn't needed, I mentioned it mainly to smooth the heat transfer into the Ti tube.)
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Re: Suppressor Build Question

Post by R1Enhanced »

White Russian, thanks for the clarification. I am getting my material list together right now. I see that on Titanium Joe's they have the 3AI-2.5V in tubing that has both .065 and .087" wall thickness. Any reason not to get the .087 instead of the .065" wall. Common sense makes me think thicker would be more durable, but also that is taken a certain percentage away from the volume of air space within the suppressor. Maybe the .065 would be perfectly fine with M and K baffles like Capt said. Not trying to beat a dead horse to you guys that are experts in this, but guys are really helping me figure all of this out. Thanks again!
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Re: Suppressor Build Question

Post by whiterussian1974 »

Capt Link is the expert here. But it seems that 0.065" thickness is fine.

If you are able to turn the 0.087" to widen the ID after the blast chamber, you needn't insert the SS liner. But if you use the liner, then the thicker wall is useless, takes up volume, adds weight, etc.

For ease of construction, I'd use .065". But I'm able to weld, and don't have a lathe. So that is my skillset to work with. Though even with a lathe, I'd still prefer to use a liner to take the "bite" before it hits the Ti. Similar concept to the "Sacrificial baffle."
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Re: Suppressor Build Question

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R1Enhanced wrote: Thu Feb 04, 2021 7:56 am Capt, once again thanks for that information, and detailed material list. That is the materials I will use once I get my stamp in. If i can bother you once more, the double butted blast chamber example that is shown, would that be bored in the Ti tube and if so any close dimensions that I could use? Meaning thickness of the butted part and maybe a little thicker dimension in between to add strength to the blast chamber. Or is that a sleeve inserted into a straight bore Ti tube, with those said dimensions? Thanks again Capt.
Butted tubes are normally swedged. (formed with dies under pressure) Theses spacers are machined for my needs. I use butted "spacers" to save weight. Blast chamber spacers/liners can be paper thin as they provide no mechanical support only protection from blast abrasion. There is no need to reinforce this chamber for the anticipated use. I have run 5.56 suppressors with .032 3AL-2.5V tube without issue.....until a new employee put it on a belt fed host.

Thick tubing allows you to bore a larger than tube ID thread bed so baffles do not hang up upon removal. A thicker than needed tube has no detrimental effect other than weight and helps to prevent distortion caused by the work holding fixtures. I use wooden machined plugs to prevent this as oval threads are not smooth.

You can collect raw material as a piece of round bar is not a suppressor part. Decide on baffle type and material then you can build fixtures to build the various parts after stamp is issued.

-CL
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Re: Suppressor Build Question

Post by R1Enhanced »

Guys you two are awesome and thank you for clarification on this build. Makes my shopping list a little easier which I did order the 17-4 today and I was waiting on your expert advice on the tube thickness, so I can get that ordered as well. I have on my Form 1 a build for 9" suppressor, what would be your advice on length of blast chamber for that total length if needed. Also I guess I should have clarified in the beginning my Blackout pistol has a 8.5" barrel. Again thank you both for your help!
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Re: Suppressor Build Question

Post by whiterussian1974 »

Capt. Link. wrote: Thu Feb 04, 2021 3:25 pm Butted tubes are normally swedged. (formed with dies under pressure)

I use butted "spacers" to save weight. Blast chamber spacers/liners can be paper thin as they provide no mechanical support only protection from blast abrasion.
Thanks for the info. I was familiar with butt welding, but hadn't thought of press-fitting.

I wonder if nano-diamonds would be cost effective as a facing material on blast chambers, or baffle face.

Austenites like Inconel are probably cheaper and easier to work with though, for now.

https://en.wikipedia.org/wiki/Synthetic ... deposition

https://en.wikipedia.org/wiki/Detonation_nanodiamond

https://en.wikipedia.org/wiki/Synthetic ... cavitation

https://en.wikipedia.org/wiki/Inconel
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Re: Suppressor Build Question

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R1Enhanced wrote: Thu Feb 04, 2021 10:03 pm Guys you two are awesome and thank you for clarification on this build. Makes my shopping list a little easier which I did order the 17-4 today and I was waiting on your expert advice on the tube thickness, so I can get that ordered as well. I have on my Form 1 a build for 9" suppressor, what would be your advice on length of blast chamber for that total length if needed. Also I guess I should have clarified in the beginning my Blackout pistol has a 8.5" barrel. Again thank you both for your help!

Chamber size and design can get very technical.
Do you wish a thermal diffuser ? What baffles are you going to use. Do you want to overbuild for longevity?

:A diffuser replaces a physical blast chamber and helps separate gas from flame.This helps lower gas pressure and temperature.
-CL
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Re: Suppressor Build Question

Post by R1Enhanced »

Capt, I am going to go with clipped 60 degree cones with skirts decreasing in lengths, and I do want to build for longevity but being this my first Form 1 build it's ok for some mistakes and or a lot of room for improvements. The materials you suggested are ordered. As far as the blast chamber having a thermal diffuser or a sleeved blast chamber, I am open to any suggestions you may have. Do they both hold up well to the pressures or is one better than the other. I will definitely look into it more. What would you suggest for cone OD to barrel ID be when I machine the OD of the cones? I hope my cover sheet is ready soon, had my sample cover sheet for about a week and half. Thanks again for any input you may have.
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Re: Suppressor Build Question

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Clipped 60* cones are a good choice that should suppress well. Don't skimp on the number of cones 12-15 close spaced is a good number. The blast baffle should be heavy .065-.080 and the rest can be .050 or less. The blast baffle is not ported or clipped, spaced .375 from inside rear cap to cone apex. The blast chamber spacer length is based on this. I would aim for a bore of .250-300 building these cones with a press fit of .003 under tube ID. Final passage size is lathe bored last!!!! (.308 +.060 =.368 min) = Final bore size.

You can lighten the stack by using titanium for half the baffles. A alternate choice is aluminum but it must be anodized.

-CL
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Re: Suppressor Build Question

Post by R1Enhanced »

Capt once again thank you, yes sir that is where my head was going as well. 270 on the bore and thanks for the # of baffles and spacing specs and material that can be used. I can't wait to get started on this and will post pics of what I have done and please give me feedback on what I can do before putting it all together to make it any better. Thanks again Capt.!!
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