What is the legality of running m-16 (full-auto) in your restricted AR (semi)?? As I understand it, the auto-sear is the only prohibited item, as would be the lower receiver modified to accept it? I can get m16 trigger group parts and want to know if these are legal. I'm sure this has been covered, but I can't seem to find it, any help?
Legality of M-16 (FA) trigger parts use??
- Thread starter eatredmeat157
- Start date
Good question, I was under the impression (and I could be wrong) that it was legal to have an auto-sear, just illegal to put it in a gun. I thought the full auto lower was the illegal part of the gun to own. I don't know about the trigger tho.
canucklehead
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M16 trigger parts are fine in a semi-auto AR lower.
There is no way you could make it full-auto without doing milling/drilling of the lower. FA trigger parts does not a FA make!
There is no way you could make it full-auto without doing milling/drilling of the lower. FA trigger parts does not a FA make!
Just going off what the RCMP firearms techs tell me. And it's not really a broad statement, it's actually a narrow one specifying one particular part
Why? You got one kickin' around?
btw, we went through this topic last week, it's on page two, I believe.
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A factory auto sear is useless in nearly 100% of semi AR15s. It requires not only the axis pin hole drilled in the proper location it requires the lower to be milled out to accept it. Semi lowers are intentionally left narrow inside to defeat simple installation. Regardless I wouldn't keep an auto sear around as it is exclusively used in prohibited firearms and thusly is prohibited itself (I recall there being some FA wording to that extent).
The drop in auto sear (DIAS) is also a no-go. About half the semi lowers on the market won't accept one anyways because the "shelf" under the rear takedown pin was intentionally left milled too shallow to prevent installation of a DIAS. There's a list at ARFCOM detailing which lowers are DIAS friendly for those that are curious.
M16 trigger, hammer, disconnector, and selector are usually okay but bear in mind that the combination of an M16 selector, trigger, and disconnector will permit the hammer to ride the carrier forward if the selector is in the AUTO position and the trigger is held. Whether this will discharge another cartridge is debatable; the purpose of the auto sear is to prevent that situation from occurring and reliably release the hammer when the bolt is locked (an auto sear does not magically make your gun full automatic, it just makes it reliable and safe in automatic mode).
The drop in auto sear (DIAS) is also a no-go. About half the semi lowers on the market won't accept one anyways because the "shelf" under the rear takedown pin was intentionally left milled too shallow to prevent installation of a DIAS. There's a list at ARFCOM detailing which lowers are DIAS friendly for those that are curious.
M16 trigger, hammer, disconnector, and selector are usually okay but bear in mind that the combination of an M16 selector, trigger, and disconnector will permit the hammer to ride the carrier forward if the selector is in the AUTO position and the trigger is held. Whether this will discharge another cartridge is debatable; the purpose of the auto sear is to prevent that situation from occurring and reliably release the hammer when the bolt is locked (an auto sear does not magically make your gun full automatic, it just makes it reliable and safe in automatic mode).
As a caution, and this has been covered in previous threads, if you put in a totally F/A trigger group and F/A bolt carrier, it is possible to get hammer follow resulting in unsafe F/A if your ammo has soft primers. The cure is to use a semi-auto disconnector (a $.50 part).
EDIT: Someone beat me to it!
EDIT: Someone beat me to it!
![-[Crosshair]-](/forum/data/avatars/m/31/31565.jpg?1718745216){kind=avatar}
Please elaborate?
The FA disconnector has a longer rear end that extends underneath the (FA) selector and when you switch it to fun mode, holds the disconnector back so it won't catch the hammer. This allows the auto-sear to do it's job of delaying the hammer release.
If you grind the tail off the rear, it prevents the disconnector from being held back so it functions normally as a SA gun.
If you grind the tail off the rear, it prevents the disconnector from being held back so it functions normally as a SA gun.
Back in the day when surplus parts were more common (trigger,disconnecter etc), you'd find one or more FA parts in the lower receiver (especially in aftermarket AR's).
When regulations changed (or more realistically, when interpretations of those regulations changed), makers got rid of the FA parts for legal/liability reasons. For those who didn't want to spend the $$ to get the semi parts, there were/are ways to grind the applicable areas off these parts so as to avoid those said legal/liability reasons. This all sums up US manufacturers experiences with the BATF, but makes sense for Canada too as our bureacrats run even more wild than down south.
In one of his AR-15 books, Duncan Long diagrams which areas to grind off.
But yes, as stated earlier, I believe the "real" prohib part is the auto sear and DIAS. Although I'm sure the other paqrts mentioned above will raise eyebrows/cause trouble even if they aren't specificqally mentioned. Thats just how it is here
When regulations changed (or more realistically, when interpretations of those regulations changed), makers got rid of the FA parts for legal/liability reasons. For those who didn't want to spend the $$ to get the semi parts, there were/are ways to grind the applicable areas off these parts so as to avoid those said legal/liability reasons. This all sums up US manufacturers experiences with the BATF, but makes sense for Canada too as our bureacrats run even more wild than down south.
In one of his AR-15 books, Duncan Long diagrams which areas to grind off.
But yes, as stated earlier, I believe the "real" prohib part is the auto sear and DIAS. Although I'm sure the other paqrts mentioned above will raise eyebrows/cause trouble even if they aren't specificqally mentioned. Thats just how it is here
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