Do-It-Yourself SBS/NFA

[DrewBegley]

Okay, I have no intention of breaking the law and have no means of actually building (or destructing?) a firearm, but how would one go about building their own short barrel shotgun?

I know there's a ton of legal issues surrounding this subject and I don't need to hear any more of them, this subject always turns ugly when people start throwing out the tax stamp, overall length, barrel length and state law issues/questions. I want to know the bare essentials of doing the deed, not the jumping through hoops.

How can someone cut down a barrel the old fashioned way and not ruin the acoustics of the firearm? I'm talkin' "No Country for Old Men" style, with a hack saw and haste. Would the barrel need to be refinished/filed in any way like polishing and reaming? What kind of saw does this job (I'm a novice carpenter and don't have background in metal working)?

I suppose I'll also repost this in the "Gunsmithing and Repairs" section as well due to the craftsmanship.
AGAIN I HAVE NO INTENT ON BUILDING THIS TYPE OF FIREARM. Just curious in the overall workings of the project.

 

[btg3]

How can someone cut down a barrel ...

Good videos at youtube. Easy to search and find.

1. Tape the barrrel to prevent errrant scratches before sawing.
2. Clamp in a suitable vise.
3. Hacksaw.
4. Square the muzzle with a handfile.
5. Clean up the raw edge with emory cloth.
6. Apply cold blue.

The above works whether you cut to 20", 18-1/2", or beyond.

Next question... "how do I install a bead sight?" (Your choice: drill-tap-sight kits or glue-on. Check out Midway, Brownells, etc))

 

[Sam1911]

How can someone cut down a barrel the old fashioned way and not ruin the acoustics of the firearm?

btg3 has you covered on how you can physically make the barrel shorter, but he didn't address your question on the acoustics.

Like it or not, shorter barreled guns are LOUD. Or at least louder than longer-barreled guns firing the same cartridge.

Surprisingly, it is possible to build a silencer/suppressor for a shotgun, and they work. They're just not real common.

But if you really care that it sounds the same once you've cut it down, I can't think of any other way to do that, unless you can find low-power, lightly loaded shells that produce less blast to begin with.

 

[CoRoMo]

I prefer a band saw. Makes for a fairly square cut and saves the elbow grease. If the barrel is ribbed, cut it at the pillar closest to the magazine's end cap. Right in front of this bead, would be the perfect spot to chop.

 

[DrewBegley]

Another page taken out of "No Country", Chigurh's silenced semi shotgun. I can't even imagine how someone would go about building a suppressor/silencer from scratch, but a buddy of mine built one back in highschool in machine shop and it worked (surprisingly) for his .223 mini-14. I'd imagine you can copy the same concept and up the anty to a 12 ga, I'd imagine the hard part would be threading a shotgun barrel.

CoRoMo: I do have an 870 WM, but no middle bead anyway. I think if I were to go about the project, I'd switch to a real cheap cylinder bore with a bead.

I was on another forum looking for this discussion (with no luck) but did see a guy post about doing the job with a rifle sighted, rifled barrel... he posted a photo where he went through the trouble of taking off the sights and cutting down the barrel. I've seen regular rifled barrels, uncut, sling loads all over the square range with absolutely no accuracy. I'm, not a big shotgun guy, but wouldn't cutting down a rifled barrel and loading no. 7 or even 00 sling out the shot like a blender with no cover?

 

[Sam1911]

Rifled barrels do tend to create wide patterns with shot, usually donut shaped with a hole in the center. That's not a positive thing.

 

[crazy-mp]

Shotguns with shot and suppressor combos are more difficult, one of the better designs I have seen used large baffles and they took piano wire and stretched it from end to end to keep the wad from grabbing and opening up. I think they had it twisted like a roll of toilet paper cylinder so it looks like rifling I don't know how much it helped with keep the wad closed but the sound suppression was pretty impressive.