Simple Silencer Design - Am I on the Right Track?

dakota.potts · July 22, 2015, 03:46 PM

The thread on the solvent trap kits got me thinking. They seem like they work halfway decent for what they are. I notice that there are both stainless steel and titanium tubes available (Threaded on both ends internally) as well as steel and titanium thread protectors and endcaps.

From what I read, all of that seems to be pretty decent, but I think I would want to go with a monolithic baffle design over the freezeplug and spacer design. It seems more durable that way.

I would want to make a monolithic baffle on a lathe, presumably out of steel. It would just be a simple cylinder with an oversized bore (probably around .375-.400") and a number of circular chambers milled out at regular intervals.

I have some ability with machine tools, but doing something like this is about the limit of that ability. I can turn items on a lathe to a tolerance with minimal runout and I can mill straight holes and paths in things.

Most would choose to leave a threaded lip on the baffle and then thread the tube directly into that. This is beyond my ability currently though and it would want to be something that I can build. Obviously I wouldn't be building the tube and endcaps in this design, but at least the baffle would be mine.

The SDtactical and other various "solvent trap" kits get around this by using a PVC pipe spacer inside the tube which snugs up to the baffles and vertical spacers. You simply drop it in and screw it together. Apparently the spacer keeps it tight enough that wandering isn't an issue.

My thinking was, could I do something similar with a monolithic baffle design? If the tube has a 1" inside diameter, could I machine the baffle to something like a .998" diameter so it would slip in with minimal tolerance but still wouldn't need to be an interference/press fit? Would the pressures be an issue in that case? The endcaps could then be sealed up against an o-ring to keep the baffle from moving vertically inside the tube.

I'm just thinking about this for now. I'm starting machine tool classes in Early August, which is the earliest I'd be able to send in a form 1 anyway. I was looking to spend about $400-450 on another project, and that's why I'm thinking in the terms that I am. Buying all of the stuff from SDtactical would put me about the same ($100 trust + $200 tax + $~125 materials). I know good stock to machine a baffle would be more.

I'm a gunsmithing student (starting machining before gunsmithing) but I won't be allowed to work on any NFA items in school, so it will all be extracurricular.

I want to make something fun, relatively cheap, to see what can be done. I would like to build some kind of a portfolio while I'm in school, and I think a project like this would be cool to include. I'm not concerned with top end performance (I obviously want it to work though) or weight, as I know these will diminish with lower cost of material. I just want something of a decent durability and usefulness. Size is not too much of an issue either.

I will use it pretty much just at the range and maybe a couple of shots a year during hunting season. Maybe in 2 gun type competitions also. Probably not for home defense, too many issues with that for me. I would like to use it on .22 (reason for needing it to disassemble for my own maintenance), .223 AR 15, 7.62x39 VZ2008. Maybe a Mosin Nagant, but that's not really important to me. Also, I have future projects in .308 and .338 Federal. Would like to use it on those if it comes to fruition but not entirely essential.

What do you think, people who have done a Form 1 silencer before?

Lark · July 22, 2015, 10:31 PM

Include a drawing; it is worth a thousand words.

I think anyone who makes a form 1 silencer should buy a lathe and make a bunch of them. A baffle stack beats a monocore almost every time. Make it all steel and weld the end caps in place. This way you can chemically clean it after each 5000 rounds of 22lr. Welding the core to the tube means you just need to press fit the core to the tube once and forget about it.

One inch wide is fine for 22lr, I would go with 1.5" wide tube for .223 to .308 calibers, 1.625" for .338 caliber.

Drill/tap threads in the rear of the mono core to attach it to the barrel.

A mono core for a high powered rifle is going to weight a lot. Baffles take a while to make, but they are worth it in the long run. A mono core or baffles are machined out of bar stock, baffles work better and weight less.

dakota.potts · July 23, 2015, 06:32 AM

I'm a college student on a pretty low budget in an apartment. A lathe isn't in the cards right now but is part of my plan for the future.

If the endcaps are welded in place, would you need an adapter for every different thread pitch?

Lark · July 27, 2015, 01:59 PM

1/2-28 to 5/8-24 adapters are easy to fine. This covers putting a 30 caliber can onto a 22 caliber rifle. You are not allowed to have extra end caps with different threads, those would be extra unregistered parts. But for some reason the ATF allows people to sell recoil boosters without controls even though they are merely spring loaded end caps.

dakota.potts · July 27, 2015, 10:01 PM

Well, I never asked anyone to explain to me how the hive mind of the ATF administration works

I'll keep that in mind though. Thanks for your input

July 22, 2015, 03:46 PM	#1
dakota.potts Senior Member Join Date: February 25, 2013 Location: Keystone Heights, Florida Posts: 3,084	Simple Silencer Design - Am I on the Right Track? The thread on the solvent trap kits got me thinking. They seem like they work halfway decent for what they are. I notice that there are both stainless steel and titanium tubes available (Threaded on both ends internally) as well as steel and titanium thread protectors and endcaps. From what I read, all of that seems to be pretty decent, but I think I would want to go with a monolithic baffle design over the freezeplug and spacer design. It seems more durable that way. I would want to make a monolithic baffle on a lathe, presumably out of steel. It would just be a simple cylinder with an oversized bore (probably around .375-.400") and a number of circular chambers milled out at regular intervals. I have some ability with machine tools, but doing something like this is about the limit of that ability. I can turn items on a lathe to a tolerance with minimal runout and I can mill straight holes and paths in things. Most would choose to leave a threaded lip on the baffle and then thread the tube directly into that. This is beyond my ability currently though and it would want to be something that I can build. Obviously I wouldn't be building the tube and endcaps in this design, but at least the baffle would be mine. The SDtactical and other various "solvent trap" kits get around this by using a PVC pipe spacer inside the tube which snugs up to the baffles and vertical spacers. You simply drop it in and screw it together. Apparently the spacer keeps it tight enough that wandering isn't an issue. My thinking was, could I do something similar with a monolithic baffle design? If the tube has a 1" inside diameter, could I machine the baffle to something like a .998" diameter so it would slip in with minimal tolerance but still wouldn't need to be an interference/press fit? Would the pressures be an issue in that case? The endcaps could then be sealed up against an o-ring to keep the baffle from moving vertically inside the tube. I'm just thinking about this for now. I'm starting machine tool classes in Early August, which is the earliest I'd be able to send in a form 1 anyway. I was looking to spend about $400-450 on another project, and that's why I'm thinking in the terms that I am. Buying all of the stuff from SDtactical would put me about the same ($100 trust + $200 tax + $~125 materials). I know good stock to machine a baffle would be more. I'm a gunsmithing student (starting machining before gunsmithing) but I won't be allowed to work on any NFA items in school, so it will all be extracurricular. I want to make something fun, relatively cheap, to see what can be done. I would like to build some kind of a portfolio while I'm in school, and I think a project like this would be cool to include. I'm not concerned with top end performance (I obviously want it to work though) or weight, as I know these will diminish with lower cost of material. I just want something of a decent durability and usefulness. Size is not too much of an issue either. I will use it pretty much just at the range and maybe a couple of shots a year during hunting season. Maybe in 2 gun type competitions also. Probably not for home defense, too many issues with that for me. I would like to use it on .22 (reason for needing it to disassemble for my own maintenance), .223 AR 15, 7.62x39 VZ2008. Maybe a Mosin Nagant, but that's not really important to me. Also, I have future projects in .308 and .338 Federal. Would like to use it on those if it comes to fruition but not entirely essential. What do you think, people who have done a Form 1 silencer before? __________________ Certified Gunsmith (On Hiatus) Certified Armorer - H&K and Glock Among Others You can find my writings at my website, pottsprecision.com.

July 22, 2015, 10:31 PM	#2
Lark Senior Member Join Date: November 28, 2012 Location: Western WA Posts: 144	Include a drawing; it is worth a thousand words. I think anyone who makes a form 1 silencer should buy a lathe and make a bunch of them. A baffle stack beats a monocore almost every time. Make it all steel and weld the end caps in place. This way you can chemically clean it after each 5000 rounds of 22lr. Welding the core to the tube means you just need to press fit the core to the tube once and forget about it. One inch wide is fine for 22lr, I would go with 1.5" wide tube for .223 to .308 calibers, 1.625" for .338 caliber. Drill/tap threads in the rear of the mono core to attach it to the barrel. A mono core for a high powered rifle is going to weight a lot. Baffles take a while to make, but they are worth it in the long run. A mono core or baffles are machined out of bar stock, baffles work better and weight less. __________________ Lark is free!

July 23, 2015, 06:32 AM	#3
dakota.potts Senior Member Join Date: February 25, 2013 Location: Keystone Heights, Florida Posts: 3,084	I'm a college student on a pretty low budget in an apartment. A lathe isn't in the cards right now but is part of my plan for the future. If the endcaps are welded in place, would you need an adapter for every different thread pitch? __________________ Certified Gunsmith (On Hiatus) Certified Armorer - H&K and Glock Among Others You can find my writings at my website, pottsprecision.com.

July 27, 2015, 01:59 PM	#4
Lark Senior Member Join Date: November 28, 2012 Location: Western WA Posts: 144	1/2-28 to 5/8-24 adapters are easy to fine. This covers putting a 30 caliber can onto a 22 caliber rifle. You are not allowed to have extra end caps with different threads, those would be extra unregistered parts. But for some reason the ATF allows people to sell recoil boosters without controls even though they are merely spring loaded end caps. __________________ Lark is free!

July 27, 2015, 10:01 PM	#5
dakota.potts Senior Member Join Date: February 25, 2013 Location: Keystone Heights, Florida Posts: 3,084	Well, I never asked anyone to explain to me how the hive mind of the ATF administration works I'll keep that in mind though. Thanks for your input __________________ Certified Gunsmith (On Hiatus) Certified Armorer - H&K and Glock Among Others You can find my writings at my website, pottsprecision.com.

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