6”x2” 304 Design .30 cal

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TreyDaniels
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6”x2” 304 Design .30 cal

Post by TreyDaniels »

Hello all,
Specific Question is in bold at bottom. First time builder been doing as much digging on here as possible to answer before asking. I’ll lay out the purpose/function now.

Dedicated .30 cal on 10.5” 7.62 AR
Pinned/welded to give 16” barrel length
Want it near or full FA although I’m too poor to be putting too much through this can at once.
Cheap. Light(haha).

Current materials procured:
4003 style 304 tube 2” OD 1.81 ID. .095 thickness
304 “dry cups” simple cone style 1.8 OD .85” width .05 thickness

I’m thinking of taking can one of two directions:

Full tube, welded end caps, baffles Tacked together(?) tightly fit. Turn down outside of tube until .05 or other suggested thickness. Con: heavy

Tubeless, 2” of 4003 can for blast chamber, 5 welded cups to reach 6”

I’m not here to ask how or why and waste time I have that info. I need to know IF THE BAFFLES ARE THICK ENOUGH WELDED TOGETHER IN TUBELESS FORM

^ this is the question I can’t find a straight answer on and why I’m posting. Full tube would be a heavy wh*re but I’ll do it if I gotta.

If I’m overlooking something or you have useful suggestions I will gladly listen. I think the material I have is worthy enough for what I will put it through and likely will build a better can if I shoot enough to compromise this one. Cost me $100 in material and if it lasts any amount over a few thousand rounds I will be highly satisfied.
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Capt. Link.
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Re: 6”x2” 304 Design .30 cal

Post by Capt. Link. »

I may qualify as a person who will give useful information, you need to start over. A short barrel 308 is a beast and will eat almost anything ahead of it. Add near full auto fire and poof you have slag. My recommendation is use a all welded all inconel tube and baffles plus many more inches of suppressor.

A realistic build would start with a much longer barrel 20-24" and slow fire.

-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!
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895
TreyDaniels
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Re: 6”x2” 304 Design .30 cal

Post by TreyDaniels »

Capt. Link. wrote: Wed Jan 27, 2021 10:08 am I may qualify as a person who will give useful information, you need to start over. A short barrel 308 is a beast and will eat almost anything ahead of it. Add near full auto fire and poof you have slag. My recommendation is use a all welded all inconel tube and baffles plus many more inches of suppressor.

A realistic build would start with a much longer barrel 20-24" and slow fire.

-CL
My apologies man, the gun is 7.62x39 not 308!
There’s a guy on here doing a tubeless one for a 10” AK in 17-4 w/ baffles about the same thickness.

I just want to know if welded 304 baffles @1.8” OD and .05 thickness with a beefy(2”x1.8”)blast chamber won’t disintegrate with a mag dump. That is the material I have on hand and I will likely buy some 17-4 material for if/when this one gives up and when I can find it in stock. I have $120 total in material for this build and I can always just rebuild with better material later.
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Capt. Link.
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Re: 6”x2” 304 Design .30 cal

Post by Capt. Link. »

Any suppressor will hold up to a mag dump or two. Read what I said to the other gent about SAG. Short barrels cause a huge amount of heat and expansion of the metal causing welds to crack and thin edges to melt.The short suppressor will not do much in the way of suppressing sound or flame.The longer the barrel the better as the gases are cooler and of lower pressure.
Inconel can be bought as drops on flea-bay to build a suppressor to handle the heat. First stage should be a flame arrestor followed by a heavy duty blast baffle and subsequent lighter baffles. These are welded and inserted into a tube. The overall build will be longer, last longer and suppress better.
I wish you luck and can give more detailed instruction on how to build this through a PM.
-CL

PS: I built suppressors for 308 and 5.56 rifles for close to 40 years. Many of these were full auto and some were overbore cartridges that eat barrels and suppressors. Most of my designs were very heavy with most having baffles widths between .250-.500. These baffles known as thick film had tremendous longevity do to heat dissipation and hardness. I use a flame arrestor, it kills the flame front making a huge difference in the performance and longevity.
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
TreyDaniels
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Re: 6”x2” 304 Design .30 cal

Post by TreyDaniels »

Capt. Link. wrote: Thu Jan 28, 2021 12:13 pm Any suppressor will hold up to a mag dump or two. Read what I said to the other gent about SAG. Short barrels cause a huge amount of heat and expansion of the metal causing welds to crack and thin edges to melt.The short suppressor will not do much in the way of suppressing sound or flame.The longer the barrel the better as the gases are cooler and of lower pressure.
Inconel can be bought as drops on flea-bay to build a suppressor to handle the heat. First stage should be a flame arrestor followed by a heavy duty blast baffle and subsequent lighter baffles. These are welded and inserted into a tube. The overall build will be longer, last longer and suppress better.
I wish you luck and can give more detailed instruction on how to build this through a PM.
-CL

PS: I built suppressors for 308 and 5.56 rifles for close to 40 years. Many of these were full auto and some were overbore cartridges that eat barrels and suppressors. Most of my designs were very heavy with most having baffles widths between .250-.500. These baffles known as thick film had tremendous longevity do to heat dissipation and hardness. I use a flame arrestor, it kills the flame front making a huge difference in the performance and longevity.
Link,
Many thanks for your expertise and knowledge in a straight ahead format. This is obviously my first foray into form 1 building and this can is mostly serving as learning process and a cheap way to get to 16” barrel w/some suppression. This is the first I’m hearing of the flame arrestor and I’ll try to do some research on the subject. I have access to Tig although it’s been a while since I’ve done it so again this can will be a learning process as I’m accruing better materials for later builds. I’ve pretty much decided to overbuild it and run it until it fails in some way or another and then use why you’ve given me and what I’ve learned into a better can. Again, Many Thanks!
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Capt. Link.
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Re: 6”x2” 304 Design .30 cal

Post by Capt. Link. »

The term flame arrestor is more descriptive than technical. Thermal diffuser is the proper term though I don't build them like they used to. I applied the fact that a flame will not pass through a hole and some knowledge from the gas industry to help break the fire triangle. Perforated disc's with a dimple at the bore hole "like a K baffle" will help deflect gas and flame. I have a bunch of pictures but can't post them for some reason ?

Thought's: Increase the barrel to 16.00" and port it for a reflex suppressor that will extend only 4.00" past the muzzle.
With the cost of 200.00$ per rebuild making it effective and bullet proof is the only way.

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!
http://www.silencertalk.com/forum/viewtopic.php?f=10&t=79895
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whiterussian1974
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Re: 6”x2” 304 Design .30 cal

Post by whiterussian1974 »

Capt. Link. wrote: Fri Jan 29, 2021 11:59 am Perforated disc's with a dimple at the bore hole "like a K baffle" will help deflect gas and flame. I have a bunch of pictures but can't post them for some reason ?
If they are on an image sharing site, just post the web addresses and I'll try to figure a way to code them so that they are visible here.
Capt. Link. wrote: Fri Jan 29, 2021 11:59 am Thought's: Increase the barrel to 16.00" and port it for a reflex suppressor that will extend only 4.00" past the muzzle.
With the cost of 200.00$ per rebuild making it effective and bullet proof is the only way.

Best CL
I think that his main goal is to shorten the barrel. Perhaps doing as Capt suggested but using a 12" barrel would fit all of your needs. Vent into the reflex volume to quench the flame and retain the highest pressure gasses, then have the baffles for the 4" in front of the muzzle.

I bit my tongue on the "replacing parts" issue. I nearly posted "sounds great, as long as you aren't in the USA" but bit my tongue. I really didn't want to get involved in any "questionable" practice. And he's already publicly stated his "constructive intent." A major No-no under the Biden Admin.... :(
The Darkest Corners of Hell are reserved for those who remain Neutral!-Dante
The Death of One is a Tragedy, a million only a statistic.-Stalin
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