Difference between M-4 and M16A2 Bollt-Firening pins

**DennisH82** · August 6th, 2010, 03:04 AM

This will be the first thread I have started and it’s because of an interesting e-mail I received last night. One of my Soldiers wrote me that the local armorer told him that he had an M16A2 bolt, bolt carrier and firing pin in his M-4 and that this was causing his primer strikes on rounds that were just being chambered and removed. He was also told that his firing pin was just a shade too long because it was an M16A2 firing pin. I have carried and shot M16A1’s A2’s and the M4 for Uncle Sam and I would like to think I know something about these weapons. I am no Armorer but I strongly believe someone is smoking some funny stuff to make the above written comments to my Soldier. I know folks like BilT who have more experience than my can answer my question below.

Is this true; are there different Bolts, Bolt Carriers and Firing pins for these weapons? Is this the cause of the primer strikes when loading and clearing a weapon?

I hope someone can enlighten me, thanks

**TJB63** · August 6th, 2010, 03:49 PM

Sounds like B. S. to me, But what a marketing concept.

~ TJB

**arjohnson** · August 6th, 2010, 04:03 PM

Bolts, carrier's and firing pins were always the same in full autos. I think at one time there was a differance between AR15 and M16 firing pins and carriers, but I do beleive now they are all being manufactured the same.

**Asmodeus6** · August 6th, 2010, 04:14 PM

Light taps on the primer on a chambered round is normal. If you held one and ever chambered and ejected a live round from it - you know that.

AK's do it, AR's do it. If you want less of a mark on the primer buy a titanium firing pin. Or get creative and find a way to put a spring in there to hold the firing pin rearward when the momentum of the bolt drives it forward while it's stripping a round.

But basically they all do it. So as to what bullshit the guy your soldier talked to thinks he's cooking up... I have no idea. Maybe he should put down the effing crack pipe.

**DennisH82** · August 6th, 2010, 10:21 PM

Between the answers here and theTACOM memo I thought this was the answer, It seem the only difference is the extractor spring is supposed to be a newer gold colored spring as opposed to the silver one. something about the lower presure difference in rate of fire. As for my Soldiers report I have never heard such stupidity, but he says thats what a civilian contractor told him. My only concern was the slightest chance that this could be right and the safety to my Soldiers, Had to check, thats what I get paid for. Thanks.