Might be better in NFA forum, but someone here will know.

In making a suppressor, is there a magic line, like with an 89% lower, where “I need to operate the machine” verses having someone make parts or assemble parts and I do that last final assembly?

My observation in the suppressor Form 1 groups is everyone talks in code.  I do t need a solvent trap.  I need a suppressor. ??

From the ATF handbook:

You could try contacting one of the SOT's like @hawkstand to see what they say.  I know he bores and clips cones, but the legal aspect of "what can be done" is best answered by someone like him.

https://www.google.com/search?client=firefox-b-1-d&q=Spectrum+Tactical+Solutions

Drill endcap to pass a bullet of the size listed on Form 1.

Everything else can be done at SOT such as boring and clipping of cones and engraving

They speak in code because zuccbook is anxious to shut down anything and everything firearm related.

You can draw your own plans and go to a machine shop and have them make your parts. So long as you stay in control of said parts (they don't leave your sight/control) it's legal.

You can buy a bunch of solvent trap parts and go to the same machine shop, to have them finish said parts. Again,  so long as you stay in control of the parts, it's legal.

You can buy a bunch of solvent trap parts and only drill your end cap ( to meet the caliber listed on the approved form). Then, send it off to an SOT, with all the untouched solvent cups, for it to be finished into an efficient design.

You can get away w/ just a hand drill and file, but a drill press and Dremel would be a step above. There are people that can custom cut your spacers or skirts (prior to the pieces becoming silencer parts) so you don't have to. There are a couple places to get jigs, for boring and clipping, that can help immensely.

In other words, it's really not that hard to finish a solvent trap kit. Just spend the time reading the trials and tribulations of others and the best ways to finish the parts kit.


Just a clarification. An SOT isn't needed for clipping or engraving.

You're right. I meant for sending it off. If you can stay in control of the parts and a machine shop is willing to let you stand there while they machine them then any old machine shop can do it.

Yeah that is just another example of incorrect info in that handbook I have been telling people to throw away for almost 15 years. I assume you did not read it, as even a newbie should be able to spot the felony and an experienced person should be able to spot the other errors.

The magic line is when it becomes a firearm. Unfortunately, the magic line is not defined in law. It is like pornography - you know it when you see it. I think it is safe to say the operation of drilling a bore hole in a cone is making a baffle.

With all respect, that really is the easy part.  If that is true, some good craftsman could fashion a ready to drill full can and avoid all the tube this and baffle that and cap whatever.

You might be right.  Well, who ever said 80% lower was good enough to not be a firearm (before 2021)?  Why not 60% ?

He is. It's a silencer when it meets the definition, same as anything else.
While I've machined plenty of lowers (2 from billet) I can't honestly say if 80 is close to an accurate percentage. It's just a number and has zero relevance.
  It either is or isn't a firearm. If you have doubt, be sure the ATF isn't going to be on the side of your innocence.

This “tube and baffle … whatever” IS a ready to drill full can.

The BATFE said.