AR15 Bolt Stop VS M16 Bolt Stop

[Thalinor]

After having the pleasure of shooting an m16, i
decided i liked the way the bolt stop worked better
then the ar15 bolt stop/release. When i shoot i
usually count my shots, so the luxury of having the
bolt stay open on the last shot is not one i really
need. Honestly, the whole added step of hitting the
bolt release is just a PITA in my opinion.

After looking at the bolt stop on my ar15, i noticed
the main difference from the m16 bolt stop was this
little added nipple. Apparently that nipple fits in a
groove in the mags and when the last round fires, it
holds the bolt open.

So my question is... Can i cut the nipple off the bolt
stop so that it will function like a m16 bolt stop?
(IE the bolt will stay closed on the last shot and i
will no longer have to hit the bolt release when
charging the rifle.)

I called the ATF and they said it was not illegal to
remove or modify the bolt catch as long as the rifle
stayed semi-automatic. I can't see how by cutting
that nipple it would cause this or any other
unforeseen issues but i am not an expert. At this
point i am more worried about breaking my rifle.

After a search online i have not found anyone who has
actually posted on this topic so i figured i would ask
someone who might know. I have included a photo
(attached to this email) which will better explain
what I am talking about.

Thanks for the info in advance.

[ColoradoGlocker]

.

[JWP]

i have a conversion ea j15 which holds the bolt open, friend has colt original 16 which holds the bolt open - i wasn't aware that the holdopen feature was missing on current .gov m16

[Thalinor]

Originally posted by JWP
i have a conversion ea j15 which holds the bolt open, friend has colt original 16 which holds the bolt open - i wasn't aware that the holdopen feature was missing on current .gov m16

Well the m16A2 i used i just pulled the charging handle and let it (and the bolt) slam shut. When the mag was empty, the bolt release did not hold the bolt open. It was nice because the whole reload task could be done with one hand. I was able to keep the other hand on the foregrip with out moving it (or reach over the rifle) to close the bolt as it was never "locked open".

There is also an article somewhere that explains the differences between the AR15 and the M16. They point out the bolt catch on the m16 being manual unlike the ar15 version that holds the bolt open after the last round.

Lastly, there is a video out there (again, i would have to look around for it) that shows some blackwater guys shooting from a roof. If you watch, when the guy goes to reload he does not move his left hand from the fore grip rather just pulls the charging handle and lets the handle/bolt snap forward. If he was changing mags with one in the tube, he would not have to charge the rifle. If the bolt on that m16 had locked open after the last round, he would not have to charged the rifle... rather just hit the bolt release. In the clip he reloads several times and the procedure is always the same.

All of this is irrelevant because i know what i was using (the m16A2) while on a military base. The line officer (or whatever the hell you call him) running the range gave us a "how to" on the rifle before using it. One thing he pointed out was the reloading procedure which did NOT include pressing the bolt release. Having an ar15 I thought this was strange till I actually got to use the rifle. The entire 3 hours i was shooting i did not use that bolt release once as there was no need.

Anyway, this was not the point of the post. I was wondering IF IT WOULD SCREW UP THE GUN by removing that nipple. That’s all!!! : )
As for why? It’s the same thing mother used to say… “because I said so” … actually it’s more like “because I want my rifle to work that way” (something mother never actually said) :P

[C9X19]

Lastly, there is a video out there (again, i would have to look around for it) that shows some blackwater guys shooting from a roof. If you watch, when the guy goes to reload he does not move his left hand from the fore grip rather just pulls the charging handle and lets the handle/bolt snap forward. If he was changing mags with one in the tube, he would not have to charge the rifle. If the bolt on that m16 had locked open after the last round, he would not have to charged the rifle... rather just hit the bolt release. In the clip he reloads several times and the procedure is always the same.

That makes absolutely no sense. If there was one in the tube, then his rifle would not be empty. One would think it's better to concentrate on hitting your targets rather than counting how many rounds are left in the magazine. I know of ZERO instructors or classes that teach you to do such a thing. Also hitting the bolt release to chamber a round is still charging a rifle.

Here is the link to the video: http://www.ifilm.com/ifilmdetail/2677403

[DJ Niner]

Thalinor,

Short answer: Yes, you can cut off the tab on the front of the bolt catch/release to make it stop catching the bolt after the last shot.

Long answer: However, this is NOT how a properly functioning M16 works. I have extensive military experience with the M16, M16A1, M16A2, GAU-5A, GAU-5A/A, and GUU-5P (last three are the predecessors to the current M4 carbine), including firing, periodic and detailed inspections, and repairs below depot level. If the weapon has not been modified, is clean/lubricated and functioning properly, and the magazine is not excessively worn, it SHOULD lock the bolt back after the last shot. If the M16 you fired did NOT lock back after the last shot in the magazine was fired, it was not functioning as designed.

I can possibly explain the video you saw, as some combat shooting instructors simplify the reloading process by teaching the same procedure for reloading no matter if the weapon is empty or partially loaded -- drop mag, replace with new mag, charge weapon with charging handle. This will ALWAYS get your weapon reloaded, whether you begin with the bolt open or closed, mag in or out, or even if the bolt accidentally closes in the middle of the reload. There are no decisions to make (how should I reload THIS time?), and no analysis of the position of the weapon's bolt is required (let's see; bolt forward, I have to charge, bolt rearward, I can just hit the button, but I don't have to, I can charge, too...). It also reduces fumbling, as there is no small button to press/hit (bolt catch/release) to close the bolt.

I'll also say if you chose to remove the tab of the bolt catch/release, I recommend you do so carefully. If you grind it off while it's still in the weapon, you run the risk of getting metal shavings and abrasive dust in the internal parts (not good at all); if you remove it to work on it, it's very easy to damage the part of the receiver where the bolt catch/release pin passes through the receiver "bumps". You'll need a thin-bodied punch of the proper diameter to tap the pin out, and once removed, the bolt catch/release spring and detent will be released from beneath the bolt catch/release. Make sure they are reinstalled properly before re-mounting the bolt catch/release.

Also be aware that if you modify the bolt catch/release in this manner, the bolt itself may start to gouge your magazine followers when it closes on an empty chamber. Normally, to get the bolt to close on an empty chamber with an empty mag in place, you have to depress the top of the bolt catch/release, which not only releases the bolt to slam forward, it also cams/presses the magazine follower downward slightly, which gets it out of the path of the bolt (because the tab you want to grind off pushes the follower down when activated). Without this tab, the follower will stay at the very top of the mag, and the bolt itself will push the follower down as it passes over it, possibly scraping off some follower material each time it happens.

I hope this info helps you make an informed decision on this potential modification. Good luck!

[Thalinor]

Originally posted by G17raider
That makes absolutely no sense. If there was one in the tube, then his rifle would not be empty. One would think it's better to concentrate on hitting your targets rather than counting how many rounds are left in the magazine. I know of ZERO instructors or classes that teach you to do such a thing. Also hitting the bolt release to chamber a round is still charging a rifle.

Here is the link to the video: http://www.ifilm.com/ifilmdetail/2677403

Counting shots is like counting cards... once you get good at it its not a conscience thing. I can count rounds w/o even thinking up to about 15; after that i sometimes get confused. Its hard to explain. Its NOT like i am actively sitting there counting... its all subconscious and does NOT take away from my shooting concentration. Again, from waht i am told its exactly like counting cards at a casino. Funny thing is i don't gamble. Oh well.

When i drill with my pistol i always "leave one in the tube" during reload. By doing this reloading is not only faster (the use of the slide release is not needed) but if a threat comes into view you are not totally screwed. As you can imagine i am 100% against mag disconnects and refuse to buy a gun that has one unless it can be removed.

With the ar15 i have not yet made it to the point of "unconscious counting" because of the 30 round mags. Again, i have only really been shooting consistently for about 2 years. Given some time and i will have the 30 rounders down soon enough.

BTW: In all cases i am taking my time and not just shooting as fast as i can down range. Stopping and talking to someone or getting distracted does not "affect" the count. Again, the mind can do anything you train it to do if you take the time to practice.

Originally posted by DJ Niner
Thalinor,

Short answer: ~

Long answer: ~

Thank you much for the reply!!!

As for the m16 i used, they were training rifles on a national guard base. I am not sure if they were just broken or had been dumbed down to make training easier. I will say that a few of the sights were totally screwed up so its entirely possible that they needed some major overhauling.

In any case. I decided to do it last night and it worked out perfectly. It took a hacksaw and a little TLC. I then filed the end down and polished it up nice. Seems to work like a charm but i wont know till i go to the range today.

I also just ordered the tactical doubled sided bolt catch just in case i get tired of the current mod.

Thanks again for the replies.

[Bren]

Standard AR-15 bolt cathes are exactly the same ones used in M-16's. While several lower receiver parts are different for full auto, the bolt stop and mag catch are the same. You shot an M-16 that had a worn or broken, malfunctioning bolt catch. You can break or file down your own bolt catch so it will malfunction on your rifle, but that's probably the worst idea I have ever heard in 23 years of shooting M-16's and AR-15's.

You seem to be claiming that it is easier to pull the bolt all the way to the rear and release it with the charging handle, rather than just release it by pushing the bolt catch. Maybe you have some kind of problem with the bolt catch that no other shooter has ever encountered, but since you can also release a locked back bolt by pulling the charging handle, just like if it wasn't locked back, and it takes less pressure to do it that way, your idea still makes no sense. Why not let the bolt lock back, then pull the charging handle to release it?

[ColoradoGlocker]

.

[B+Shooter]

I just read through this thread and I am a little freaked out that you purposely marred your weapon to match a malfunctioning weapon. The other posters have it right. A functioning weapon will lock the bolt back on an empty follower, and pulling the charging handle with a loaded mag will send the bolt home. After years of shooting an M16A2/M4, I just learned the smoothest/fastest way to function the weapon, usually using the bolt release.

Having said that, The AR15 platform does a wonderful job of being "tricked", and being that this is America, you are free to have the weapon the way you want it. Let us know how it worked at the range.

[agalb]

Just for argument's sake, there are other (successful) weapon systems that do NOT incorporate a last shot hold open feature, 2 prominent ones being the AK and the MP5 (although the MP5-10/.40 does have this feature).

The point is, a last shot bolt hold open device is far from a necessary feature on a weapon system.

[SW.FLA.glocker]

I don't understand why you would want to do this. As stated before, the m16 you fired must have been malfunctioning since the part in question is the exact same in both platforms. I always found it easier to just slap the left side of my weapon to release the bolt and continue on with my mission. As for the video you have sited of the Blackwater guys, the sniper clearly uses his thumb once or twice to release the bolt after inserting the magazine. A couple of other times he uses his thumb and it seems nothing happens. That is why he makes a second attempt but uses the charging handle this time. I suspect the bolt became stuck due to grit from the enviornment.

I would have left it alone btw.

[JWP]

btw if you want to have the function w/o mods, buy a betac 100 rd magazine - the follower is designed to not hold the bolt back on empty