Shorten a barrel without accidentally making an SBR?


December 16, 2011, 09:59 PM
Hi, this isn't really an NFA question, rather one about avoiding accidentally making an illegal NFA weapon.

I have the opportunity to buy a barreled Mosin Nagant action in poor shape for very little money.
Bubba has already chopped the barrel (badly, with a hacksaw by the looks of it) down to about 19" or so, but thankfully he didn't try to drill for scope mounts or attempt to bend the bolt.
This isn't one of those super-rare 1-in-17,000,000 Mosins that are super-valuable :D so I thought it might make a nice project gun.

What I would like to do is trim the barrel down further, then add a permanently welded-on muzzle brake, giving a total length of just >16".
Add an ATI synthetic stock, and I think I'd have a fun little gun for not much money.

However, it has occurred to me that as soon as I cut down the barrel, and before I weld on the brake (even if it is a matter of minutes) I will have temporarily manufactured an SBR.

The only way around this that I can think of is to remove the barrel from the action, transfer the action to a friend, cut the barrel, weld on the brake, then get the action back and screw the barrel back onto it.

I don't have the means to remove the barrel from the action, and paying a gunsmith to do this for me would turn the project from 'fun' into 'pointless'.

The alternative is to simply make the barrel 16.25" and find the shortest muzzle brake I can, but that wouldn't be my first choice.

Is there a provision in the law to allow me to do such a thing, or is this project an absolute no no?

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Jim K
December 16, 2011, 10:51 PM
And why do you insist that the result be "just" 16"? Only because it is fun to play games with the law? Get real.


December 16, 2011, 11:04 PM
This is not a place to mess around. Cut and re-crown at 16.25, and enjoy the rifle.

December 16, 2011, 11:05 PM
If the action/receiver is the serialized part, it is the firearm. It doesn't have to have a barrel or stock attached to be defined as such. Since it started it's life as a rifle, that action/receiver is a rifle, even without its barrel and stock.
-remove the barrel from the action, transfer the action to a friend-
I can't find the thread, but I remember a thread from another forum regarding these two discussions:
The discussion revolved around the subject of the lone stripped receiver/action. Since the action/receiver is a rifle, once you remove the barrel, that action/receiver would then fall below the 26" overall length requirement, and this rifle action/receiver would not have a barrel of 16" or greater. In the discussion that I was referring to, this would cause it to fall under NFA regulated territory.

I can't find that thread, but that's the extent of the discussion that I recall. On the bright side, I'm certain that the ATF doesn't regulate this area as closely as I've described.

Carl N. Brown
December 16, 2011, 11:22 PM
I don't think overall length of a bare barreled action without a stock or some kind of rear hand grip is counted by ATF as a short barrel rifle (under 26" overall) otherwise I would be in violation of NFA everytime I remove my M1 carbine barreled action from the stock for routine cleaning.

December 16, 2011, 11:25 PM
@ Jim K:
I didn't say 'just 16"', I said 'just > 16"'.
'>' is shorthand for 'greater than'.
What I meant was a little over 16" to be on the safe side; ~16".25" is what I had in mind as leaving an extra quarter inch is generally what is considered to be a good safety margin. I mentioned this a little further down in my post.

By the way, '~' means 'approximately'.

Thanks everyone else for the replies, they confirmed what I suspected.
I'll trim the barrel itself to a minimum of 16.25" without the brake.

Edit: @Carl M Brown:
That is a very good point, I didn't think about removing a rifle stock for cleaning etc. In many cases that would indeed take the rifle below the 26" OAL, which is very similar to the scenario I proposed.

Has there ever been a legal precedent or an ATF letter about this type of thing?

December 16, 2011, 11:28 PM
And why do you insist that the result be "just" 16"? Only because it is fun to play games with the law? Get real.

as im sure this can be reworded better, i think a better answer is available.

as above mentioned you would be better off cutting to 16.25 and recrowning. unless someone else has a more accurate answer of course, im very interested in where this one goes. i too have a butchered up mosin that could become a fun carbine!

December 16, 2011, 11:48 PM
I don't think overall length of a bare barreled action without a stock or some kind of rear hand grip is counted by ATF as a short barrel rifle (under 26" overall) otherwise I would be in violation of NFA everytime I remove my M1 carbine barreled action from the stock for routine cleaning.
That's exactly what I was referring to. The action, if serialized, is considered the "firearm", and if it's always been a rifle, that action is technically a rifle. The discussion that I remember brought up the fact that this firearm (action) no longer has a barrel with a 16+" length or an overall length 26+". I agree that, the ATF doesn't count this as an NFA violation, but as far as I recall, this is how the written law is stated. The ATF never holds one position for too very long after all.

December 16, 2011, 11:49 PM
If you are really worried about being in possession of a SBR between cutting the barrel and welding and pinning a flash hider on, have no fear. There is a thing called constructive intent. You have the receiver and you have a barrel less than 16" in your possession you are in violation of the law, because you have the ability to produce a illegal SBR. Its like having M16 parts and a AR, either one by themselves is ok, but legally you cant own both.

Good luck trying to break the Mosin barrel off, the ones I have messed with were put on by two drunk Russian's and a mule. But I am sure somebody will say how easy they are and how they can almost take one off by hand. :rolleyes:

December 17, 2011, 12:04 AM
@crazy mp:
I'm not sure I follow, you said to have no fear, but then talk about constructive posession?
It's not that I'm worried that I would get into trouble in the short time between the cutting and the welding, (that would be some REAL bad luck) but even after the fact, the rifle would still be 'evidence', ie it would be obvious that the barrel had been shorter than 16" at some point.
I'd rather just play it safe unless I find out for sure that temporary configurations during maintenance/gunsmithing don't count as manufacturing an NFA weapon.

As to removing the barrel, I too have heard horror stories and have no intention of attempting it...

Aaron Baker
December 17, 2011, 12:13 AM
Good lord. There's a whole lot of overthinking going on in this thread. The ATF is not standing over your shoulder watching you gunsmith. And that's the most important answer. Although as a legal matter, you should not chop a barrel that is IN an action below 16" even if you're about to weld back on a permanent extension, the chances of jack-booted thugs busting your door down during that hour-long operation is nil. (I'm not advising you to do something illegal--just giving you a reality check.)

On a practical note, since I've shortened a Mosin barrel before, I would suggest just cutting it at 16 and 1/4 inches and recrowning. If you're not going to remove the barrel from the action or go to a professional gunsmith, then you're not going to be able to put decent threads on the barrel to add that muzzle brake anyway. So skip the brake. The fireball is fun to watch without one.

As for BK's comment and whatever previous discussion was had, it is nonsensical. If you remove the barrel from a receiver, that doesn't make it a short-barreled rifle. It's not a "barreled" rifle at all without a barrel. If that were the case, you couldn't ever sell a bare action unless it was on a Form 4.

You have to have a barrel attached for it to be an SBR. Even a registered SBR with a greater than 16 inch barrel isn't CURRENTLY an SBR. It's only a short-barrel rifle when it is both short-barreled AND a rifle at the same time. (That's why people with SBR'd AR15s can cross state lines without ATF permission as long as they have a 16"+ upper on the rifle until they return to their home state.)

As for the question of whether you make a short-barreled rifle every time you remove a 16" barreled action from its stock (where the action is less than 10 additional inches by itself), you don't. That's also just nonsense. What you have then is rifle parts, not a rifle.

Although they sometimes issue stupid rulings, the ATF is ultimately constrained by what a court will allow them to get away with when challenged. And no one is ever going to be convicted for manufacturing an illegal SBR for taking their barreled action out of its stock.


December 17, 2011, 12:31 AM
I agree. I often sell stripped receivers after all. I was only referring to the way the law is written. As you said, it's nonsensical, but I think that is how the law is worded, but again, the enforcement agency doesn't enforce it this way. Thank God.

December 17, 2011, 10:14 AM
I'm sure the fireball would be spectacular, but I'd like this rifle to be more than a novelty.
I thought that if I added a brake and a recoil pad, I could have a carbine that will be fun to shoot for more than just a few shots, and also that my rather more recoil-sensitive wife could enjoy shooting too.
Actually, now I've given it a little more thought, I think it might be a better idea to have a 16.25" barrel with a removable muzzle brake so that I don't annoy people at the range!
Also, a removable brake would make cleaning up after shooting corrosive ammo easier.

December 17, 2011, 11:43 AM
if you have somebody with a lathe,you should be able to chuck it up w/out removing the barrel muzzle breaks.they can do the barrel work,or you can replace the old one with a crterion

December 17, 2011, 12:17 PM
think about it this way. people take ,<16" barrels and permantly attach muzzle breaks to clear 16" all the time. ASK the atf if you are that worried about it. it will take them forever to answer most likely, but it will be in writing. Quit asking people who you cant run afoul of and go to the people who will cause the problem if they dont like it.

December 17, 2011, 01:10 PM
My take on this: Intent goes both ways. If you have a flash hider/muzzle device you are planning on using, and a method of attaching it to the barrel that meets the ATF guidelines, then you have the INTENT of making this a legal rifle in the eyes of the ATF.

So, if you take the barrel out of the stock, then go ahead and cut it down, crown it, mount the muzzle device and perm attach it in order, as expediently as possible I have a hard time believing ANYONE would have issue with that.

For the sake of argument, why aren't we afraid of taking a bolt action out of a stock? If you TRULY BELIEVE that the ACTION=GUN, then when you take the action out of a stock, you could have made a "Weapon made from a rifle" which is as equally taboo in the NFA 5320.8. (Read 2.1.4 Weapon made from a rifle. A weapon made from a rifle is a rifle type weapon that has an
overall length of less than 26 inches or a barrel or barrels of less than 16 inches in length.) Why aren't we all worried about strip cleaning our firearms? If at an intermediate step you end up with the action and barrel less than 26" total length, you have a "Weapon made from a rifle." How many of us have been arrested for strip cleaning our bolt guns?

I contend that it's because INTENT must be proved. You have all the parts to make a legal firearm in the end, and that is your INTENT.

That's my take. IANAL, so take it with a grain of salt.

December 17, 2011, 01:18 PM
Yeah, good point.
The reason I posted it here rather than ask the ATF was in case someone had already asked them or a legal precedence had already been set.
It's not worth the risk or hassle to me, I'm just going to cut/crown the barrel at a legal 16.25" and quit worrying over a 2" or so difference.
As I said above, I'm quite into the idea of having a removable muzzle brake so I can take it off and avoid upseting the people next to me at the range.
I sure wouldn't want to be shooting next to a 16.25" barreled Mosin with a brake- having hot .22 casings down my collar is annoying enough! :D

December 19, 2011, 12:02 AM
I think you're smart to leave it 16.25 inches. After all, you never know when a weld could pop loose and then where are you?

One more point: I think the fireball will be VERY impressive with a 16.25 inch barrel. The break isn't going to do anything about that. And as far as your wife shooting it? Take along something to pull her shoulder back into joint, short barrel or not. That is unless her name is Olga and she uses red shellac for nail polish. ;)

December 19, 2011, 12:15 AM
If you want to go with a short(er) barrel cut it put your brake, comp etc. back on it asap, don't drive across town with it at 14.5 inches, don't take 500 pictures and do minute by minute updates on Facebook.

I was telling you what the letter of the law said, about constructive intent. Heck most people have enough ingredients in their home to make bombs and meth but they don't get charged with manufacturing.

December 19, 2011, 11:36 PM
Er, if your wife is recoil sensitive, you might be better off spending another $100 on a full up Mosin rifle - the extra weight will reduce the recoil impulse more than the extra length of bbl will add to it. (SMLE #5, short bbl SKS)

If you figure out how to get the bbl off, let me know. I'm trying to figure out how to desolder a Marble peep sight off my cocking piece so I can swap firing pin springs @ the moment.

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