M16 bolt carrier question
- Thread starter brentn
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briansmithwins
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Any and all AR15 parts fit the M16 bolt carrier. BSW
Wolfman_556
Member
Everyone at AR15.com say you can use the M16 BCG with no problems UNLESS of course you change the AR over to a select fire configuration.
You need the M16 BCG for full auto because it is heavier. An M16 BCG does not make your AR a full-auto version unless you change it further to full auto capability.
You need the M16 BCG for full auto because it is heavier. An M16 BCG does not make your AR a full-auto version unless you change it further to full auto capability.
MMcfpd
Member
Nope, perfectly legal as is; if you buy a new Colt 6520, 6721 or 6920 that's what you're going to find inside it.
TexasRifleman
Moderator Emeritus
As mentioned Colt ships their semi's with them installed. Somewhere out there is a letter from Tech Branch to Colt basically stating that it was fine, but the usual warning to be careful and not get too carried away with M16 parts.
Here's a piece of it, you can dig around if you want to see the whole thing. Letter sent to Colt in 2005:
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I treat ARFCOM with the same credibility as Wikipedia, probably 90% correct, but not something I'd bet money or jail time on
You need an M16 BCG because it has the trip for the FCG toggle. It is heavier because of the additional metal. They will often add a heavier buffer on full-auto versions (particularily the M4's) to slow the bolt down which, in turn, drops the ROF to more controllable levels. It also helps retard the cycling on M4's a little because the closer gasport results in higher operating pressures which equals higher bolt speeds and can cause more wear-and-tear and reliability issues such as extractor jumping.
Thanks for the info, the BATFE have been a bit indecisive on this issue and its nice to see some documentation from them on the matter. For years it was often viewed as possibly being "intent to manufacture". Maybe someone finally found out how a machine gun works and have stopped basing the criteria on one part or because a gun "looks scary"
TexasRifleman
Moderator Emeritus
Oh the rest of the letter still has plenty of that I'm afraid, but in the end they finally have to agree that a BC won't make the thing go full auto.
The whole thing is just silly as we all know.
I wonder if the decision about M16 parts in an AR15 came about from Thompson Center Arms' lawsuit regarding the interchangeability of their rifle stocks on to their Contender pistol frames.
A judge ruled that just because you own a Contender pistol, owning a rifle stock does not make it an SBR. You have to have the stock installed with a sub-16" barrel to be an SBR.
A judge ruled that just because you own a Contender pistol, owning a rifle stock does not make it an SBR. You have to have the stock installed with a sub-16" barrel to be an SBR.
Zach S
Member
As stated above, the BATFE has been indecisive about it. One member at arfcom said they once replied that no M16 spefic parts can be use in an AR, and another he also has another reply that said the bolt carrier is ok.
Currently, most colt-pattern 9mms come with SMG bolts. Garrison Mfg, RRA, and Colt. Dont know about Bushmaster. They all probably get their bolts from CMT anyway.
Currently, most colt-pattern 9mms come with SMG bolts. Garrison Mfg, RRA, and Colt. Dont know about Bushmaster. They all probably get their bolts from CMT anyway.
Some people reccomend milling about 1/16 off the bottom of the bolt just as a CYA measure. Its still heavier than the AR15 bolt, however after milling that 1/16 off of it, it wont trip the autosear, so its not an M16 bolt.
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THE MACHINIST
Member
any machine gun part ,hammer,auto sear,disconnector,selector,bolt is recognized by the atf as a machine gun only ar 15 parts should be used.
Zak Smith
Member
This is laughable since the bolt is identical.
Also, if what you say were true, all those items would be serialized and registered-- they are not.
How about the barrel? Front sight base? Barrel extension? Pistol grip? Receiver extension?
-z
Outlaws
Member
So how come Colt sells their rifles with an M16 bolt carrier?
Has anyone actually confirmed this? I haven't seen any civvie-spec Colts with an M16 bolt, I suspect that if this is true it may have been for the "LEO/GOV USE ONLY" models made during the ban which wouldn't be subject to the same ATF regulation scrutiny that a commercial model would be.
I'm aware of that. But as previously mentioned, Colt got an "exemption" letter during the ban ('95) to cover their butts on the issue. IIRC Colt was selling primarily to LE and gov't buyers during the ban so I'm betting that the letter was a contigency in the event that they got into civilian hands either through expiration of the ban in '04 or sale through a LE supplier, hence Colt wouldn't be found guilty of manufacturing an unregistered machinegun. However, in civilian hands the ATF would likely take a less favorable view. Colt also uses a blocked receiver which may give them some latitude on the issue. Putting a full-auto BCG in a non-blocked gun would put you dangerously close to "intent to manufacture". Just my .02
Zak Smith
Member
The bolts are identical. You are mistaken.
Since you are in CA and probably don't get to see either an M16 or an AR15 too often, let me break it down for you.
The AR15 BCG has a notch cut in the bridge on the carrier to clear the area where the toggle would be on the M16. The bridge on the M16 BCG is intact and trips the toggle when the bolt closes when an M16 is switched to auto.
Zak Smith
Member
A FA bolt carrier alone cannot make an AR-15 fire full auto, period, full stop. Constructive intent requires enough parts to make a FA be present, and would not apply to this case unless the person also possessed other M16 fire control parts sufficient to built a full-auto rifle ("properly" or through malfunctions).
The assertion that "any machine gun part [...] is recognized by the atf as a machine gun" is also false.
Firstly, this would imply that an M4 barrel would either "be" a machinegun in itself, or adding an M4 barrel to an AR15 would make it a MG, which is false. In actuality, they are indentical.
Secondly, if it were true that those items were literally machineguns in the eyes of the ATF, then every one of those items would be required to be serialized and registered-- which they aren't.
The assertion that "any machine gun part [...] is recognized by the atf as a machine gun" is also false.
Firstly, this would imply that an M4 barrel would either "be" a machinegun in itself, or adding an M4 barrel to an AR15 would make it a MG, which is false. In actuality, they are indentical.
Secondly, if it were true that those items were literally machineguns in the eyes of the ATF, then every one of those items would be required to be serialized and registered-- which they aren't.
Zak Smith
Member
Please read more carefully. You are describing the bolt carrier. The question posed was about the bolt itself.
Actually, I've seen both ... in California, fancy that. You seem to be confusing the bolt with the bolt carrier.
"More Signal, Less Noise.....please" - Rich Lucibella
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