Im about to buy a PSA BCG to finish my build, and i noticed it said auto. I read somewhere this just means its hollowed out more (for full auto use) but i couldn't get a clear answer whether or not it would still work with a semi trigger group

 

thanks for the help as always.

Nope. In fact, the M-16 BCG is preferred by many shooters. It's not "hollowed out more", it actually contains more material toward the rear of the bolt, making it stronger. Check out this video for a decent explanation:

 

 

And for good measure, this one covers the legality of using the M-16 BCG in an AR-15.

 

 

HTH.

From what u understand it should not be an issue.. I know allot of ar builds that specifically request m16 Bolts...

 

 

/\ answered right before me

To answer the original question

 

http://www.ar15.com/.../AR15-M16Parts/

Bolt Carrier

The M16 bolt carrier will have about a 2" closed section at the rear that actually trips the auto sear in full-auto fire. Semi-auto versions have either a reduced closed bottom section (about 1/2"), or a completely open bottom (made so that an adapter to M-16 configuration cannot be installed).

 

 

 

Another difference in the bolt carriers is the additional metal removed on the underside to expose the collar of the firing pin. This is intended to catch the hammer and prevent firing if the carrier is not fully forward when the hammer releases. This occurs if the hammer is "riding" the carrier back (i.e. no auto sear is holding back the hammer). On the M16 bolt carriers, the firing pin collar is not exposed.

There are some "hybrid" carriers that do not have this area open and yet only have the 1/2" closed bottom section in the back. There are others that appear to be M16 carriers, but apparently have had 1/4" of the rear "sear trip" section milled, and so do not qualify as M16 carriers because they cannot trip a sear.

 

 

 

 

And since BigHayden brought up about the legality of them heres the letter from the ATF about them

 

 

awesome thank you guys, i honestly hadn't even given thought to a legality issue but very good info to know

..It is not unlawful to utilize a M16 machinegun bolt carrier in a semiautomatic AR15 type rifle. ...

 

Sheesh, what a tortured double negative. Would it have killed Mr. Spencer of the ATF to write "It is legal" instead?

Heres another pic where you can see the difference

 

Edited October 22, 201214 yr by alowerlevel

Sheesh, what a tortured double negative. Would it have killed Mr. Spencer of the ATF to write "It is legal" instead?

 

Actually, his phrasing is correct, even if it doesn't sound like it should be. The government can only define things that are illegal (IOW unlawful), so has to say that there is no law against it, or "not unlawful".

...The government can only define things that are illegal (IOW unlawful), so has to say that there is no law against it, or "not unlawful".

 

Not going to belabor this, but the assertion that the government can only define what is illegal, and not what is legal, makes zero sense to me. The ATF has used the phrase "it is legal" in other publications, for example:

 

...6) Are SAWs and LCAFDs

marked “Restricted law enforcement/

government use only” or “For

export only” now legal to sell to

civilians in the United States?

 

Yes. SAWs and LCAFDs are no

longer prohibited. Therefore firearms

with the restrictive markings are legal

to transfer to civilians in the United

States and it is legal for nonprohibited

civilians to possess them.

All civilians may possess LCAFDs. ...

David Olofson thought his rifle was legal so beware!

 

Sent from my DROID2 GLOBAL using Tapatalk 2

David Olofson thought his rifle was legal so beware!

 

Sent from my DROID2 GLOBAL using Tapatalk 2

 

What does he have to do with any of this? IIRC he loaned his rifle to someone, the rifle malfunctioned and went full auto for a few rounds then jammed. Then he got shafted by the government/courts. Had nothing to do with m16 BCG, more likely just worn out FCG parts.

David Olofson thought his rifle was legal so beware!

 

Sent from my DROID2 GLOBAL using Tapatalk 2

 

David Olofson's rifle also completely emptied a magazine with one trigger pull when tested by the ATF. (Yes, I know, I know, it was a malfunction, the rifle had recalls out for it, the ATF couldn't get full auto fire with military ammo so then tried ammo with softer primers. Fact remains, an AR type that doesn't malfunction won't go full auto with just an M16 carrier).

David Olofson thought his rifle was legal so beware!

 

Sent from my DROID2 GLOBAL using Tapatalk 2

 

What is this BS??? The OP asks a legitimate question. He gets a definitive answer, including a letter from the ATF and then you feel it necessary to jump in and obfuscate the issue with non-relevant BS. To use terms you're familiar with: Asked and answered, your contribution is not relevant.

 

Adios,

 

Pizza Bob

I'll explain why I made that remark, because it is important.

 

Olofson had an AR that was built using several purportedly legal M16 parts. That was how Olympic Arms made his AR. It malfunctioned, as we all know, and everyone here knows that the parts were not the reason why the gun malfunctioned. Everyone here knows. The prosecutor, jury, and judge? The public watching television news? They don't know how an AR works. They probably are either incapable of actually understanding mechanically how it works, or if they are able to understand it, in all likelihood they don't care and are not going to try to figure it out. All they knew is the thing fired full auto, had full auto parts in it, therefore Olofson must be guilty.

 

So my point, and I should have set it forth at length the first time, is that sure you are free to put M16 parts in your gun if you want to, but god forbid the thing malfunctions and fires off a string at the range in front of a bunch of witnesses. Because then you have a real problem explaining to the judge and jury and media why you decided to use machine gun parts when you were building it, if you didn't intend for it to be a machine gun. The jury who decides your case will not be composed of engineers, but ordinary people.

 

Certainly there is a very small chance of anything like that happening to you. But you ought to be aware of it in making your decision. As always you are free to do what you want, subject only to results and consequences.

Not going to belabor this, but the assertion that the government can only define what is illegal, and not what is legal, makes zero sense to me.

 

If something is not prohibited by law, then it is legal by default in the U.S. The government does not have the authority to define what is legal, only what is illegal. Laws are definitions of criminal activity, not definitions of legal activity.

 

The ATF has used the phrase "it is legal" in other publications, for example:

 

Well, it's a good thing the ATF has never been wrong before.

If something is not prohibited by law, then it is legal by default in the U.S. The government does not have the authority to define what is legal, only what is illegal. Laws are definitions of criminal activity, not definitions of legal activity.

 

Unless you're talking about NJ Gun laws. Then everything is illegal, and they define what is legal... hahah...

I'll explain why I made that remark, because it is important. Olofson had an AR that was built using several purportedly legal M16 parts. That was how Olympic Arms made his AR. It malfunctioned, as we all know, and everyone here knows that the parts were not the reason why the gun malfunctioned.

 

What you fail to understand is the case was NOT made on the parts. It was made on the BATFE's definition of a machine gun and the fact that they pushed for, and got accepted by the court, a definition that does not account for malfunctions. Combine that with modern BS jury instructions, and a jury with no spine or motivation to enforce common sense, and you get a bad case.

I wonder then, would it be preferable to have an M16BCG, or an AR15 BCG in a semi-auto rifle. As in, which one is more durable, or otherwise grants greater performance?

Here I am not going to argue this since like I said, you can take your chances if you want to, but here is the trial testimony of the ATF firearms examiner in the Olofson trial giving testimony about putting M16 parts in an AR-15. We all know this testimony is wrong, but nevertheless this is what will happen if your gun malfunctions and they find M16 parts in it. On the basis of this testimony any jury will put you in prison no matter what you say. Hence the peril of putting M-16 parts in an AR-15 firearm and the reason why I posted in the first place. As always, you are free to do what you want.

 

 

Jury Trial - 1/7/08

Witness: Max Kingery

 

Q. And how many firearms approximately have you examined in

your official capacity to make that determination, that is,

whether the firearm qualifies as a machine gun?

A. As evidence I've examined several hundred firearms, maybe

approaching a thousand firearms that would have fit into the

machine gun category.

Q. Okay. And if I show you what's been marked as Exhibit 1 in

this case, do you know whether you've had an opportunity to

examine this particular firearm?

A. Yes, sir, I have.

Q. And how do you know that?

A. From the serial number. I looked at it earlier also as it

was sitting on the table and verified that it's the same firearm

that I examined.

Q. Okay. And do you know how many times you've had an occasion

to examine that particular firearm?

A. Well, not counting today three occasions.

Q. And is it true that you examined that particular firearm

specifically in the course of performing your duties as an FEO?

A. Yes.

Q. And do you recall when the first test was?

A. It was in October of 2006.

Q. Okay. And how did that test come about? How did you first

come into contact with that gun?

A. The item was submitted to Firearms Technology Branch as

evidence, and it was assigned to me for examination.

Q. Okay. And once it was assigned to you, you took possession

of it, right?

A. Yes, sir.

Q. And what did you do that?

A. Well, I examined it to see if it had been modified in any

way, or if any parts had been installed into it to convert it

into a machine gun.

Q. And what did you find upon that examination?

A. When I examined this firearm I found that there were four of

the fire control components, it had been assembled with machine

gun components for four of the firearm components.

Q. And what four components were those?

A. The trigger, the hammer, the disconnector, and the selector

switch.

Q. Okay. And based on your training and experience, what is

the effect of having those four components, those four specific

components be M-16 parts rather than AR-15 parts?

A. When installed to an AR?

Q. That's correct.

A. It would make the weapon fire automatically, or allow it to

fire automatically.

Q. And when you say allow it to fire automatically, you mean

allow it to fire more than one round with a single pull of the

trigger?

A. Yes, sir.

Q. And, therefore, constitute a machine gun?

A. Yes, sir.

Q. I show you what's been marked as Exhibit 9.

Now, Exhibit 9 is a document entitled, AR-15 to M-16

Conversion, right?

A. Yes, sir.

Q. And it indicates on page 2, if you turn to that, there's a

notice at the bottom I believe that indicates that the purpose

of the manual is to instruct individuals as to how to convert a

nonautomatic to an automatic firearm, right?

A. Yes, sir.

Q. And --

THE COURT: Counsel, please note that document is not

currently in front of the jury. Do you wish to have it

displayed?

MR. HAANSTAD: I'm sorry, yes, Your Honor, please.

THE COURT: Can the jury see that clearly?

Go ahead.

BY MR. HAANSTAD:

Q. And if you turn to page 10 of that manual. Now, at the top

of page 10, it's captioned, AR-15 Parts?

A. Yes.

Q. And it shows five different fire control components, right?

A. Yes, sir.

Q. And you had mentioned that four fire control components were

M-16 rather than AR-15 in this particular firearm, right?

A. Yes, sir.

Q. And which four are those?

A. The hammer, the selector, the trigger and the disconnector.

Q. Okay. And again, based on your training and your

experience, is it necessary to replace all five of these AR-15

parts that are listed here in Exhibit 9 in order to make an

AR-15 fire automatically?

A. No, sir, it's not necessary to replace all five.

Q. Okay. And you testified that during your October 2006

examination of this particular firearm of Exhibit 1, that you

noted that four of these five were changed, right? Or I'm

sorry, four of these five were M-16 rather than AR-15

components, right?

A. Yes, sir.

Q. Okay. And based on the fact that those four components were

M-16 rather than AR-15, did you have an expectation as to

whether or not that firearm would qualify as a machine gun?

A. I expected that it would fire automatically, yes.

You keep bringing this case up, but yet it says nothing about him having a m16 BCG in it.

You do realize that a good % of the rifles for sale today use the m16 profile bolt carrier right? Buy any new DD, BCM, Colt, Noveske, Spikes, PSA, etc rifle and it will have the m16 style BCG in it. You really think if it was a legal issue that any of those companys would take the chance of putting them in their rifles?

 

BTW its just as easy to get a gun with all ar15 parts in it to malfunction and go full auto.

You keep bringing this case up, but yet it says nothing about him having a m16 BCG in it.

You do realize that a good % of the rifles for sale today use the m16 profile bolt carrier right? Buy any new DD, BCM, Colt, Noveske, Spikes, PSA, etc rifle and it will have the m16 style BCG in it. You really think if it was a legal issue that any of those companys would take the chance of putting them in their rifles?

 

BTW its just as easy to get a gun with all ar15 parts in it to malfunction and go full auto.

 

That brings up a question, what if your gun misfires, and fires off multiple rounds? Are you immediately a felon? Dumb question, I know, but I'm curious.

 

I wish this was a bit clearer, this issue. I would assume that many parts made for the M16, that do not make it full-auto, would make an AR15 more durable, since they'd be milspec parts, and they'd likely be cheaper if they were surplus or something. I would imagine there would be some advantages to putting innocuous parts from an M16 into an AR..