Making your own M4

[dirtymike1]

I could really think of anyway to title this thread but I guess that is pretty close. I was just speaking with a SGM in my office and he was saying that he would really like to have an M4, a true M4. But since they are post 86 he knows that he can't buy one.

So my question is this, if he were to buy a M16 could he then covert it to an SBR? This will be true only the proper channelswith all forms and tax stamps, but we just didn't know if you can do that to a NFA firearm legally.

 

[highorder]

If he buys a transferable M-16, he can do whatever he pleases with it, like add a legitimate M-4 upper.

 

[Zoogster]

So my question is this, if he were to buy a M16 could he then covert it to an SBR? This will be true only the proper channelswith all forms and tax stamps, but we just didn't know if you can do that to a NFA firearm legally.

A machinegun is a machinegun under the law.

Machineguns are not held to most additional arbitrary limits like barrel size, whether it fires from a stock or not, has grips in various locations, etc etc


The lower is the registered machinegun in most m16s.
They can have any length barrel, can use a stock or not etc
You don't have to SBR a machinegun.
It is not a rifle by law, so does not become a SBR with a different barrel, it is a machinegun and remains a machinegun.



In fact now my own curiosity is peaked by my reply. If you put an upper that fires a caliber over .50 on it does it become a destructive device or need a destructive device tax stamp, or does it remain a machinegun?
If you convert it to a .75 bore diameter full auto firearm is it still just a machinegun?

 

[dirtymike1]

Zoogster, that's exactly what I'm getting at. There has to be a point where it fails to be a machinegun and start falling into a gey zone...

So, just for the sake of argument here, if he picked up the M16 lower, he could remove the stock and put on a 8in barrel and make himself a pseudo full auto pistol? I just see a point where the jack boot thugs will come in and say you can do that because they just made up the rule that you can't.

And you make a good point as well, with the proper machining skills and know how you could feasble use the m16 lower to operate a large cal. "cannon" so to speak. I think with how vauge the laws are written the ATF will make a translatio that states you can't have these things just becasue you are smart enough to make them yourself.

 

[TexasRifleman]

So, just for the sake of argument here, if he picked up the M16 lower,

Stop right there. If it's a registered M16 lower then it's a machinegun. It can't be a pistol, an SBR, or anything else. It's a machinegun.

There has to be a point where it fails to be a machinegun

Nope.

Because of that it can be configured any way he wants without regard to stocks, barrel length etc. The law is very clear on that, there's no grey area. If it's a machinegun the door is wide open to any configuration you want.

As for the caliber question and DD's, I'd want to see Tech Branch answer that. I suspect they would say that a registered machinegun with a DD upper would require an additional tax stamp but I'd like to see their argument in the law for that

 

[Ian]

If it's full auto and over .50 caliber, it is both a machine gun and a DD, and requires two tax stamps - or at least that's my understanding. I think the ATF used to register such things (like full-auto 40mm grenade launchers) as just machine guns, but have changed their minds on it in the last decade.

 

[Aaron Baker]

So, to summarize...

You've got (as categories) machineguns, destructive devices, SBRs, SBSs, AOWs and silencers/suppressors.

• If you own a machinegun, you don't need an additional stamp for it to be an SBR or AOW (or even an SBS if you can convert it to shoot a shotshell).
• You do need an additional stamp to put a suppressor on it.
• You may or may not need an additional stamp to shoot a non-sporting caliber over .50 caliber (destructive device). Ask the Tech Branch of the ATF.

Similarly, if you own an SBR, I believe you can put a forward grip on it even if you take off the stock, because it's already registered as an SBR, so it's neither a rifle nor a pistol under the statutes and so the ATF's crazy interpretation of "pistol-becomes-aow-when-forward-grip-attached" doesn't apply.

Anyone have any corrections to that? I think this is good information for people that want to get an answer to this question later on down the road, so I just wanted to summarize it well.

Aaron

 

[RyanM]

From the ATF's handbook:

Certain destructive devices may also meet the definition of machinegun because in addition to having a bore diameter of more than one-half inch the weapons are capable of fully automatic fire. ATF treats NFA firearms of this type as both machineguns and destructive devices. The weapons are coded as machineguns in the NFRTR with an annotation that they are also destructive devices. Any such weapons manufactured on or after May 19, 1986 are subject to 18 U.S.C. 922(o). In instances where a weapon of this type is being transferred, it is imperative that State and local laws where the weapon is being transferred do not prohibit possession of destructive devices or machineguns.

Given that they're registered as machine guns with an annotation that they're also destructive devices, I have no idea if you'd need to re-register as a dual classification, or if a letter notifying them of a change of caliber would be enough.

In my inexpert opinion, though, I'd say that a machine gun which shoots shotshells would be a destructive device in addition to a machine gun, given that most box mag fed semi-auto shotguns are DDs.

 

[dirtymike1]

Thanks for all the great info guys. I've only just started becoming interested in firearms and the laws surrounding them. I will pass along this info to the SGM today!

 

[DoubleTapDrew]

One way to find out is when you send in the form 4 on your M16 lower or RDIAS put in those larger calibers as well in the caliber box. IIRC the MG designation trumps all others in regard to barrel length and rifle/pistol but haven't heard the argument for over .50 cal on a MG.
Does anyone make an upper that will fire something over .50? Is the mag well wide enough to accomodate/feed such? A full auto .600 NE sounds so horribly impractical...I love it!

 

[Aaron Baker]

In my inexpert opinion, though, I'd say that a machine gun which shoots shotshells would be a destructive device in addition to a machine gun, given that most box mag fed semi-auto shotguns are DDs.

You know, it's interesting that you say this, since the Saiga line of semi-auto shotguns, based on the AK action, are not DDs. They're apparently sporting, according to the ATF.

If that's true, then I'm sure someone has taken a registered AK receiver and built it up with Saiga parts. Sure, it's a little harder than switching AR uppers, but it's not impossible to drill out the rivets on an AK and put all new parts on the receiver.

Voila... full-auto 12 gauge.

Aaron

 

[dirtymike1]

DT-Only thing for an AR that I know of is the .50 beowolf, which isn't considered a DD IIRC. Unless you were to make the AR a belt fed weapon, that seems to be the limit on large cal for it as far as I know, but I've been known to be wrong in before.

AB- you bring up a good point that the Saiga 12, 20 and 410 are DD. I can only guess becaseu of the setup that it's not considered a DD but you can still do conversions on them... This is where teh BATF laws confuse the hell out of me

 

[TexasRifleman]

This is where teh BATF laws confuse the hell out of me

Can't make sense out of something written by insane people

 

[dirtymike1]

Hahahahahahaha well now that you put it that way