Cutting off a barrel to make a single shot upper?

[Robanada]

I know this is the semiauto/gas operated forum, but I thought it might be more relevant since my question is primarily concerned with the gas system of an AR:

I would like to build a single shot upper for an AR pistol. To my knowledge, this means that it must not have a gas system, and also cannot have a threaded muzzle. I thought about buying a barrel and welding on a muzzle device, and welding shut the gas port.

Now I'm wondering: Could I just buy a full-length barrel with a rifle length gas system, and cut the barrel shorter than the gas port? That way I'd end up with a barrel that's >6" and <16" (necessary for the AR Pistol) and has no gas port/block for a gas system, so it'll be single shot. It'll be ugly as hell, but that wouldn't bother me. It wouldn't need to be pretty, it wouldn't even need sights, it just needs to be able to fire a single shot, and a single shot only. (One could also get a 0 round sled that's locked in with a mag lock).

Would this barrel, installed into an upper, function? Or would it blow up in my hand for some reason? I also don't want to run afoul of any laws, so if cutting down a barrel before it's made into an upper would be illegal in some way, please let me know.

This is all hypothetical, of course. I have no intention of doing this- I'm just asking for my own education.

[glockman19]

Just plug the gas port.

[Robanada]

Wouldn't I still have a threaded muzzle? I thought pistols couldn't have those here.

[glockman19]

Wouldn't I still have a threaded muzzle? I thought pistols couldn't have those here.

Epoxy a threaded barrel cap.

[Robanada]

Great idea! Sounds like the better option.

But just to humor me- would the other way work?

[glockman19]

Great idea! Sounds like the better option.

But just to humor me- would the other way work?

Don't know...maybe.

I'm going to buy or build a bolt action upper on a Fulton Armory side cocking upper. You can buy one

http://www.fulton-armory.com/fariflecal556mmupruniversalprecisionrifle-3-3-2-2-2.aspx

[Bullets&Whitewalls]

I don't think the threaded barrel is an issue because the mag is outside of the grip anyway. So you have to have a fixed mag to not run afoul of AW status. There's a ton of threads though that cover this. Don't take my answer as gospel

[Ki6vsm]

Single shot?? As in, no magazine and you feed in one round at a time by hand? Like a Ruger #1?

From what's above, it looks like you're just wanting to disable the semi-auto capability and create manual-only operation... which is a cool idea. But it's not "single shot".

[9mmContagion]

Doing so would create a bolt action rifle, which to the best of my knowledge would NOT fall under the "Semi-Auto Assault Weapon ID Chart." You would just have a bolt action that looks like an AR. But you wouldn't be able to have a barrel shorter than 16". As far as the Pistol side, you'd have to follow the pistol flow chart, which I'm not all too familiar with. But I do know there's something about the magazine being outside the pistol grip, which is where you'll problem will arise

Edit: just followed the flow chart, and appears to be fine from what I can see

[Quiet]

Wouldn't I still have a threaded muzzle? I thought pistols couldn't have those here.

Summary for handguns:
Threaded barrel not installed (by itself) = legal
Threaded barrel installed on a bolt-action pistol = legal
Threaded barrel installed on a lever-action pistol = legal
Threaded barrel installed on a pump-action pistol = legal
Threaded barrel installed on a revolver = legal
Threaded barrel installed on a single-shot pistol = legal
Threaded barrel installed on a semi-auto pistol with a fixed 10 round or less magazine = legal
Threaded barrel installed on a semi-auto pistol with detachable magazines = illegal [PC 30515(a)(4)(A)]

[boopiejones]

to make a semi auto into a bolt action, would the easiest way be to remove the gas tube and turn the gas block upside down?

[9mmContagion]

to make a semi auto into a bolt action, would the easiest way be to remove the gas tube and turn the gas block upside down?

Yes that would work

[Ki6vsm]

to make a semi auto into a bolt action, would the easiest way be to remove the gas tube and turn the gas block upside down?

Provided your gas block has set screws on the bottom, it'd probably work fine. The rear set screw would cap the barrel's gas port. You might need to use a short hand-guard, because a flipped gas block wouldn't fit inside some of the newer, slim HGs. I guess you could grind off the gas-tube ridge, but then this is no longer the easiest (lowest time and labor) solution.

You might be able to get away with just moving the gas block forward a 1/16" or a hair more so that the holes no longer overlap.

Next easiest thing would be to simply tack weld the barrel's gas port closed. Only reason it's not THE easiest way is that not everyone has the ability to do this.

The next easiest thing to do after that would be to weld up the holes on the gas block and install it in its normal orientation. This method would likely be the most preferable since it doesn't change the barrel itself, and yet could still be seen by the DOJ as a more "permanent" disabling of the rifle's semi-automatic action.

[SVT-40]

to make a semi auto into a bolt action, would the easiest way be to remove the gas tube and turn the gas block upside down?

Not a legal solution.

All that would mean is you have a "broken" semi-auto, because all you have to do to "repair" the semi-auto function is turn the gas block back around and replace the gas tube so the rifle functions as a semi-auto.

Weld up the gas hole, or get a new barrel without the gas hole.