AR-15 short barrel question

[Trent]

I've got a couple of non-attached 14.5" barrels from my old defunct gun shop left over, and I'm in the process of building up some AR-15's.

Are those 14.5" barrels legal to use on a non SBR if you attach a flash suppressor that extends them to 16" overall?

Does the flash suppressor have to be PERMANENTLY fitted (tack welded) or do you use just do it normally, with crush washer(s)?

 

[TurtlePhish]

You can attach a muzzle device that brings them up over 16", but it must be permanently attached. The simplest way to do it that I've seen is blind pin and weld.

 

[Trent]

That sounds like a PITA... considering I don't weld.

Guess I've got to make a choice to sell these, or pay someone to modify them..

What's the going rate on a carbine length 14.5" chrome moly thin profile barrel w/ barrel nut, round grip, and a standard tower front sight /gas block nowadays..?

 

[back40]

the flashhider must be permanently attached and give an overall barrel length of at least 16".

 

[HOOfan_1]

That sounds like a PITA... considering I don't weld.

Guess I've got to make a choice to sell these, or pay someone to modify them..

What's the going rate on a carbine length 14.5" chrome moly thin profile barrel w/ barrel nut, round grip, and a standard tower front sight /gas block nowadays..?

What brand? Chrome lined? cold hammer forged or cut rifling?

 

[TurtlePhish]

Any friends with welders? I'm sure you can find someone to do it. It's a couple-minute job.

If you're REALLY desperate, I can weld. The cost of shipping probably makes that more of a hassle than it's worth, though.

You could probably get a little over a hundred bucks per barrel if you're patient.

 

[Trent]

HOOfan - unsure, these were bought from an ex-FFL who was retired at a gun show. My partner and I bought 34 barrels, and a bunch of other AR parts. (I still have a lot of odds and ends from that deal; a 50 cal can full of front sight /gas blocks, 100+ magazine releases, etc, etc..)

I have 11 barrels left from my old shop. 8 are for AR-15, 2 of which are 14.5 cut in the profile to accept an underslung grenade launcher, the other 6 are 16" of various profiles and gas length (car and mid). The 16" I'll use.

1 is for an AR-10, chambered in 243.

1 is an in-the-white barrel chambered in 7.62x39 for an AK47 build I haven't got around to yet (been sitting there for 6 or 7 years).

The "odd man out" barrel is a quick change barrel for an LMT (lewis machine & tool) monolithic rail upper which had a special quick change barrel system. I have no intention of getting one of those, so I'll probably throw that one up for sale sometime too.

But, the fate of those are for another day. Today I'm trying to figure out what to do with the 14.5". I have a friend who welds for Caterpillar in their local factory, I'm sure he could knock it out. You mount the flash suppressor, bore a hole in to it and the barrel, press in a pin, weld, and grind flush, right? Or do I have that process all screwy? Drilling in to the barrel would be the part that makes me nervous.

 

[hardluk1]

Maybe talk to a wielding teacher at a community collage if you have one near by. All you need as about 2- 4 second hits with a tig in the pin.

 

[TurtlePhish]

You mount the flash suppressor, bore a hole in to it and the barrel, press in a pin, weld, and grind flush, right? Or do I have that process all screwy? Drilling in to the barrel would be the part that makes me nervous.

Correct, don't worry about the drilling. Just drill into the threads, give it a tiny bit more, and done.

 

[Walkalong]

Does it have to be blind pinned and welded, or is blind pinned OK? If it is, that solves the welding part.

Anyone with a MIG welder can do it easily though. It would be fast and easy. They could do a handful in minutes. Connect ground, two or three second weld, next.....

 

[rjrivero]

Does it have to be blind pinned and welded, or is blind pinned OK? If it is, that solves the welding part.

Anyone with a MIG welder can do it easily though. It would be fast and easy. They could do a handful in minutes. Connect ground, two or three second weld, next.....

Blind pinned implies pinned with weld over the top, doesn't it?

The answers can be found in ATF 5320.8. They describe the only ways in which a muzzle device can be "permanently" attached and apply to the overall length of the barrel. Specifically chapter 2.

 

[rcmodel]

Blind pinned implies pinned with weld over the top, doesn't it?

Not to me.

It implies a pin with only a hole on one side going in, and no hole on the other side to drive it back out once driven in.

Of course, you could drill it out.
But you can drill a welded pin out too.

rc

 

[Trent]

My buddy who works at Cat says he can knock it out for me easy-peasy..

Thanks for the reference link RJ, that'll help make sure it gets done right!

 

[mortablunt]

Yes, the flash suppressor must be permanently attached (non-removable) and the combined length of barrel+suppressor must come out to >16 inches.