Building a suppressor

[kealil]

Hello all!
I’ve been looking at getting a suppressor in the near future. I have looked at many options but none have really caught my fancy. I found several resources that demonstrated the fabrication of one’s own suppressor and every video showed processes that I can do (and have done for previous projects) in my garage. So I have decided instead of buying one, I will form 1 and build a suppressor.

I have a few questions however, both legal and technical:

1. The videos I viewed demonstrated several different materials for building suppressors. Some used Titanium, Aluminum, Stainless steel, etc but none described the specific material type. Which stainless? What type of titanium tube? Welded? Seamless? How thick for the walls? Is there a list of common materials used for the various components of a suppressor with the needed technical data? Maybe I’m overthinking it but I like to get specific anytime I working with metal.

2. I understand that I cannot start building my suppressor until my form 1 is approved but after it is approved are there any limits to the modification of my suppressor? For instance, If I design and build the baffles into configuration A but decide that configuration B would be more efficient can I then replace the A baffles with B baffles? I’m fairly sure the length would probably be fixed due to the form 1 but what changes(if any) can be made after initial fabrication.

I understand that some of these questions may be obvious but this is my first foray into anything NFA and don’t want to make any mistakes.

To give a more complete picture of the suppressor I’m wanting: I want my suppressor for use primarily with my 300blk but want to use it will my 556 and the 308 I will eventually own. I’m not too concerned with weight but I do plan on using it to hunt eventually. I will also be shooting cast bullets almost exclusively out of it.

Thank you all for any assistance.

[DanTSX]

What is your experience welding titanium or aluminum? Do you know good threading from bad? Barrel contricity?


There is an excellent DIY subforum over at silencertalk.com.n I'd hate to immediately pass you off to them, but they are the experts. My recommendation is to start with a more simple design for your first foray. Steel tube, steel end caps, freeze plugs, etc. It isn't rocket science. You are essentially building a car muffler straightened out, but the materials and welds have to be right, and it has to mount straight while being true to the plans on your form 1.


There isn't any problem using a 308 can for 5.56 except that it will be very heavy for 5.56 unless you go with an exotic metal and baffle stack. You can shoot subsonic 300blk out of a strong 9mm pistol can.


Go for it. You'll learn a lot. At most you'll be out $350-$400 including the stamp.

[Elkins45]

being true to the plans on your form 1.

You don't have to submit plans to build a Form 1 silencer. All you have to tell them is caliber, length and serial number.

[Lark]

I've made several silencers in the last few years. from 22 to 50 cal.

Which stainless? What type of titanium tube? Welded? Seamless?

304 and 316 S works fine for baffles and tubing. I don't know anything about titanium. I will never make another take apart can again. All of mine eventually got stuck together and I can't chemically clean them to take them apart due to the aluminum construction.

I'm going all stainless with welded end caps in the future. Lighter and stronger, period. Chemical cleaning works fine without taking them apart. Stainless is just a bit heavier than aluminum for the light duty cans.

How thick for the walls? Is there a list of common materials used for the various components of a suppressor with the needed technical data?

At least .020" for 22lr, .035" for 5.56 and .065 for .308 to 50 bmg. I use full thickness for the blast chamber on cans less than 50 caliber and turn down the rest of the length by 20-30 percent to reduce weight

I understand that I cannot start building my suppressor until my form 1 is approved but after it is approved are there any limits to the modification of my suppressor?

Repairs can make the length a bit shorter. Changing the bore and any parts replacement by the maker is prohibited. Parts can be replaced by an FFL/SOT class 2.

For instance, If I design and build the baffles into configuration A but decide that configuration B would be more efficient can I then replace the A baffles with B baffles? I’m fairly sure the length would probably be fixed due to the form 1 but what changes(if any) can be made after initial fabrication.

You are stuck with the baffles you made the first time; make them right.

I will also be shooting cast bullets almost exclusively out of it.

If it is all stainless you can ultrasonically clean or chemically clean. Aluminum must be mechanically cleaned after taking it apart. Any can used with 22lr or cast ammo will quickly build up lots of gunk in it requiring frequent cleaning. Keep track of the weight and clean every few thousand rounds.

High powered jacketed rounds make the silencer self cleaning.

Plans are not required except for prototypes, never send them in. Never check the "prototype" box on the form.

If you have a lathe, then freeze plugs are a waste of time. Use 60 degree cones instead.