AR-15 M16 Triggers, Legality and Availability?

There is no need arguing anything here. It has been discussed to DEATH about how a hammer following a bolt home will not detonate the primer. With the hammer riding the firing pin, the pin will protrude out of the bolt face BUT when it contacts the primer (even the SOFTEST primer) the pin will be pushed back towards the hammer. The hammer will yield because pushing back a spring loaded hammer takes less force than denting a primer.

So no F/A. NONE. All you got is a uncocked rifle.
 
You have 3 members trying to explain this to you, I will give it one last try!
I is the BCG that trips the sear releasing the hammer when safe to do so and to ensure the hammer has enough spring force to detonate primer.
If you don't get that I can't help you.
 
No. It won't....
I have had everything installed. FA bolt carrier and complete FA trigger set from a batch of M16 surplus kits irunguns brought in years ago (minus the sear obviously and a lower that would even mount it). I installed the FA USGI trigger set in my restricted commercial semi auto Armalite lower. The selector would go to the auto setting and fire one round. Keep in mind I also had an old Colt FA bolt carrier on my rifle/upper.

You end up with a live round in the chamber and a dead trigger ie you have to manually #### it and eject the live cartridge in the chamber to chamber another cartridge/#### the hammer again then you pull the trigger and repeat etc
It WILL NOT go full auto unless you have a FA lower and the complete auto sear installed in it to delay the hammer. Without the sear holding the hammer to delay it/and the bolt to trip the sear later in the bolt travel sequence, the hammer will simply follow the bolt forward as it rides over the hammer in a semi auto lower. It does not strike the firing pin, it merely rides up and rests on it. It happens fast but in all the shooting I did with many different types of ammunition it never once went full auto.

Stop spreading misinformation based on lack of mechanical understanding of the firearm and creating pointless panic for nothing please.....

Also as an addition it is literally impossible to have an out of battery initiation of a cartridge in the AR15 design. You can quote the technical specifications and design of Stoner himself for that. The hammer cannot be released to strike the cartridge primer with enough inertia/force to fire it until the bolt is fully forward and engaged in the locking lugs of the barrel extension. This is also the same reason you can't fire full auto in a semi auto lower with a FA bolt and FA trigger set (minus the sear installed obviously) The hammer is released by the sear in a true full auto M16 just before it is locked in full battery, it is timed so that the back of the bolt trips the sear and the hammer is released a millisecond before the bolt locks in the barrel extension, the hammer has to travel the full distance in order to strike and actually initiate the primer. It is released as the bolt is still moving forward but it is timed so that the bolt will be fully locked and the hammer falls with full force thanks only to the sear timing this to precision. The bolt clears the hammer and is locked in battery just before the hammer travels the full unimpeded distance and does what it's supposed to do.

Travis we went thru this before when you ordered your parts from IRG.
We tried it again this summer! I stand by what I say. Perhaps you did not get a repeated fire with your assembly, but that DOES NOT make my statements and info incorrect. I DO understand the function of each part individually, and as part of the assembly, so don't try to be condescending to me and attempt to explain a system you obviously don't understand. A sear does not create F/A function, only time it properly. I am VERY familiar with the weapon having had one since they were 'available over the counter in hardware stores everywhere' in the 70's. I guess I have had more fun than you that's all. Perhaps you can exchange your parts.

Would be nice if an armorer would jump in and add some professional comments.
 
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When the DIAS was flavour of the month in the US, there were folks who set up their rifles with all M-16 parts, except for the DIAS. Figured that they could drop it in, easily remove it. With the DIAS in place, the rifle was selective fire. Removed, the hammer would follow the bolt forward if the selector was rotated all the way. As mentioned above, this should not cause the rifle to fire. BATFE figured out early on that if ammunition with particularly soft primers was used, the rifles would fire bursts. Apparently handloads were used. Burst fire was sufficiently predictable that they could make a prosecution.
 
Neither does a FA parts kit and FA BCG as you had stated in your earlier post.
The sear is inteagral to full auto operation!

Not at all. It is only 'integral' to the 'properly timed' full auto operation'.

Please indulge me for a moment.
1st, remove the upper from your AR and deal with the lower only.
With the (F/A) selector ( all fire control parts being F/A) in the fire position pull the hammer back with your thumb until it locks in position. It is being held in position thru the engagement of the front of the (F/A) trigger unit with the little lower hook in the back of the (F/A) hammer. If you were to squeeze the trigger at this point (and not release the pressure, the front of the trigger would rotate down away from the hammer hook and allow the hammer to move foreward to the normal firing positon. If you continue to squeeze the trigger and pull the hammer back as if the carrier was recocking it, the hammer does not catch on the front of the trigger now as it is still rotated out of the way, but does catch on the (F/A) disconnector hook at the middle hook of the hammer. The disconnector locks the hammer from returning foreward (to hit the firing pin) and stays locked until you release the trigger which allows the hammer to pop off of the disconnector at the same instant that the lower hook reengages the front of the trigger, and is ready to fire again.
Now rotate the sector to the F/A position and again pull the hammer back with your thumb. Again it is locked in place exactly as it was in the semi auto mode. This time if you were to squeeze an hold pressure on the trigger, it would fall foreward as before, but now on it's return travel it will not lock with the disconnector hook as the disconnector has been rotated backwards on its axis by the repositioning of the selector. With your thumb you can now move the hammer fully backwards and fully forewards at ease and can do so until you release the trigger again, where upon it will engage by the lower hook with the front of the trigger.
If you had a sear (DIAS or Mil spec) installed, it's ONLY function is to engage the top hook of the hammer and hold it back (to keep it from free firing) until the F/A carrier trips it and releases it to fall foreward to strike the firing pin. IF the trigger is released during the process, the carrier will trip the sear which again disengages from the top hook of the hammer. The hammer though immediately gets caught by the lower hook engaging with the front of the trigger and is not allowed to fall foreward.
Without the sear the only mechanical difference in operation is that the hammer (being able to freely rotate back and forth without hooking anywhere) will be rubbing up against the bottom of the carrier as it speeds by and eventually is allowed to fall fully foreward and will/can contact the primer with sufficient (heavy spring) force to fire the cartridge. On a genuine F/A carrier there is NO exposed collars of the firing pin to jam the hammer. The risk of an out of battery occurance is slim (but real), as the locking lugs should be fully rotated just prior to the carrier being far enough foreward for the firing pin (which has the force of the hammer behind it) to be contacting the primer.
 
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When the DIAS was flavour of the month in the US, there were folks who set up their rifles with all M-16 parts, except for the DIAS. Figured that they could drop it in, easily remove it. With the DIAS in place, the rifle was selective fire. Removed, the hammer would follow the bolt forward if the selector was rotated all the way. As mentioned above, this should not cause the rifle to fire. BATFE figured out early on that if ammunition with particularly soft primers was used, the rifles would fire bursts. Apparently handloads were used. Burst fire was sufficiently predictable that they could make a prosecution.

Yes, and you can bet that it would be prosecuted here in Canada too.
Just make sure you don't have a F/A carrier installed, and have fun.
 
Oh dear lord, enough already. The sear is there for a reason in the AR, AK, and many other designs. Without it, the AR hammer will ride the bolt forward, and MAY trip off the round the rifle is chambering. Probably won't, unless the primer's soft. We all get that it's possible. But it is not reliable full-auto. AK system will do something very similar with a FA trigger group and no auto sear. Not true full auto either. Let it go. FA parts plus FA carrier without auto sear does NOT equal reliable FA. Sorry.
 
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No it won't.
You still need the FA sear which is not legal to install and requires the auto sear hole drilled into the receiver.
You can have all the other parts there as it still is semi auto only.

Well, its more than just drilling out the auto sear hole. You'd also have to machine out the "jog" in a semi-auto lower. Basically it has to be same width as the FCG all the way to the take down pin step up.

Yeah, I've spent too much time looking at blueprints. What can I say, i'm geeky like that.
 
Oh dear lord, enough already. The sear is there for a reason in the AR, AK, and many other designs. Without it, the AR hammer will ride the bolt forward, and MAY trip off the round the rifle is chambering. Probably won't, unless the primer's soft. We all get that it's possible. But it is not reliable full-auto. AK system will do something very similar with a FA trigger group and no auto sear. Not true full auto either. Let it go. FA parts plus FA carrier does NOT equal reliable FA. Sorry.

It does equal charges. Read the beginning of the thread. That's what the guy is wondering.
 
It does equal charges. Read the beginning of the thread. That's what the guy is wondering.

Oh, for... the lower parts minus the sear are completely legal, and the only thing a FA carrier can do that a SA carrier can't is TRIP THE GOD DAMN AUTO SEAR. The stupidity of this entire thread is starting to piss me off.

With the above in mind, your comment on page 1

"make sure you don't also have a F/A bolt carrier in your upper, or it WILL "go fast"!"

is completely moronic.


(times like this I wish I was a mod...)
 
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Oh, for... the lower parts minus the sear are completely legal, and the only thing a FA carrier can do that a SA carrier can't is TRIP THE GOD DAMN AUTO SEAR. The stupidity of this entire thread is starting to piss me off.

With the above in mind, your comment on page 1

"make sure you don't also have a F/A bolt carrier in your upper, or it WILL "go fast"!"

is completely moronic.
Exactly. I do agree with you.
 
Oh, for... the lower parts minus the sear are completely legal, and the only thing a FA carrier can do that a SA carrier can't is TRIP THE GOD DAMN AUTO SEAR. The stupidity of this entire thread is starting to piss me off.

With the above in mind, your comment on page 1

"make sure you don't also have a F/A bolt carrier in your upper, or it WILL "go fast"!"

is completely moronic.

It seems the auto sear itself is NOT illegal. If it were I doubt Dlask would be supplying them in their m16 parts kits.
The illegal part would be the prohibited lower receiver with the autosear cutout/pin drilled.
 
How can a semi auto go full auto when it missing a hole and a spot for the auto sear to go... ?

Marstar sold M16 kits because you cannot physically install them without breaking the law and modifying your lower.
 
It seems the auto sear itself is NOT illegal. If it were I doubt Dlask would be supplying them in their m16 parts kits.
The illegal part would be the prohibited lower receiver with the autosear cutout/pin drilled.

True. Owning the auto sear is completely legal. Installing it, not so much.
 
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The risk of an out of battery occurance is slim (but real), as the locking lugs should be fully rotated just prior to the carrier being far enough foreward for the firing pin (which has the force of the hammer behind it) to be contacting the primer.

Pull out your AR15 BCG. Extend the bolt. Now hold down on the firing pin.
Start collapsing the bolt and tell me when the firing pin starts to protrude from the bolt face.

The firing pin physically cannot protrude past the bolt face until the bolt is rotated to the lock position and until the bolt has retracted into carrier. Impossible. It doesn't matter when the hammer falls or if the hammer rides the carrier home. The firing pin is unable to protrude past the bolt face until the bolt is locked and retracted. It was purposely designed this way.

So it is NOT POSSIBLE for the gun to fire out of battery (assuming you have a cam pin). Even if you don't have any auto sear or DIAS. The closest you might get is a slam-fire which is not an OOBI because the bolt will be locked when it happens.

Also, an auto sear is not illegal (unless you have it installed in the gun, which at that point you'll have made the gun F/A). however, a DIAS IS illegal, regardless of if you have it in the gun or not.
 
I am an armourer for a tactical unit that uses the hk416, I think that this was a very good thread, I enjoyed reading it. I'm not being sarcastic, I thought it had good info. Some of you guys really know your stuff, my compliments,, John
 
Oh, for... the lower parts minus the sear are completely legal, and the only thing a FA carrier can do that a SA carrier can't is TRIP THE GOD DAMN AUTO SEAR. The stupidity of this entire thread is starting to piss me off.

With the above in mind, your comment on page 1

"make sure you don't also have a F/A bolt carrier in your upper, or it WILL "go fast"!"

is completely moronic.


(times like this I wish I was a mod...)

Actually, the semi carrier IS the 'thingy' that WILL jam the desire of your AR to shoot F/A with an F/A fire control group! IT is designed to to prevent this, if you look at the bottom.
I NEVER said ANY of the parts in question were illegal in Canada. But possessing a complete unit that CAN successfully empty your clip, is!
The guy was asking questions about the system, and I answered.
If you don't like the conversation...don't read it! Again, I stand by MY statements, based on actual experiences, not just stuff off of Google.
And yes, unfortunately this has taken on a life of its own and should have gone to PM's. I apologize for my part.
Regards
 
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