Is the ar 15 supposed to do this?

[ziconceo]

Noticed that every time I load a round using the bolt release there is a little detent on the primer. Is that supposed to happen? Maybe my return spring is bad?

Thanks for any insight.

[CK_32]

Yes.

Free float firing pin.

Firing pin get slammed and pokes the primer. Reason military uses harder primers. Some guns slam fire soft primers so something to be aware of. But usually it doesn't happen. All mine do it.

[stix213]

AR-15's have free floating firing pins, so when the bolt closes the firing pin may lightly hit the primer of the round being loaded. This can cause a small detent on the primer as you have described. There hasn't been a problem of settings off rounds prematurely from this (though it isn't impossible, and has probably happened, I'm just not aware of it), unless your firing pin is somehow stuck in the forward position I suppose. If you see a detent likely depends somewhat on your gun and somewhat on the primer used in your ammo.

[ziconceo]

Ah okay, I've just never noticed it before. I'm using cci magnum pistol primers. Perhaps I should go with some wolf next time

[ExtremeX]

Its normal, I use CCI #400, #450, #41, and Tula 223, 556, SRM 556... Never tried pistol primers... you should look up the cup dimensions for thickness.

They all leave a dent, never had an issue with slam fires.

Just make sure you properly seat your primers, I preference is a hand priming tool vs on press priming...

[Sniper3142]

This happens with the AR-15 style of firearms.

Which is one of the reasons folks are advised to never chamber a live run until/unless you actually need to. Practice with Practice (dummy) rounds only. Slam-fires have been known to happen with non-military primers.

[jrpowell3]

When I was in Iraq, everytime we went outside the wire we went condition 1 on the M4, obviously that leaves the little dent on the primer. Never had a slam fire. After a few times getting chambered, you just shift that round to lower in the mag when you go to clean your magazines.

[CandG]

If you were to chamber a round at home, is it a good idea, then, to ride the charging handle forward, and then whack the forward assist to make sure it's in battery?

[Merc1138]

If you were to chamber a round at home, is it a good idea, then, to ride the charging handle forward, and then whack the forward assist to make sure it's in battery?

It's also a good idea to keep it pointed in a safe direction, just like you would do with any other firearm while chambering a round, rather than assuming one particular firearm is going to slam fire(over something completely normal), and instead treat them all the same way.

[patriot_man]

Yes, it's normal.

Certain designs eliminate this by having a spring such as the HK416.

[CandG]

Could this potentially result in firing 2 rounds with 1 trigger pull, when the bolt pushes the next round into the chamber? Just curious... I had never heard of the firing pin bouncing off the primer in AR's before.

[fritztkatt]

Could it? Technically yes. Especially if for some reason you had ridiculous firing pin protrusion (very unlikely). Every single military rifle I've seen puts a light dent in the primer when you chamber a round. My m4gery does it as well. Haven't had a slam fire with anything I've fed it though. Haven't heard anyone having one either. Just to be on the safe side, I do keep it condition 3, just like military SOP.

[Merc1138]

Could this potentially result in firing 2 rounds with 1 trigger pull, when the bolt pushes the next round into the chamber? Just curious... I had never heard of the firing pin bouncing off the primer in AR's before.

Unless it's some proprietary design with a spring loaded firing pin or something, it's so common that it isn't worth discussing except once in a blue moon when someone new to the platform notices it, and everyone basically says the same things already posted in this thread.

[barrage]

Yes.

Free float firing pin.

Firing pin get slammed and pokes the primer. Reason military uses harder primers. Some guns slam fire soft primers so something to be aware of. But usually it doesn't happen. All mine do it.

What he said. My AR15 does this, my M16 did this when I was in the Army, and my M1A does this as well. Perfectly normal operation.

[barrage]

Ah okay, I've just never noticed it before. I'm using cci magnum pistol primers. Perhaps I should go with some wolf next time

CCI primers are fine, if not superior for your application. From my experience and word of mouth from the old timers, CCI are some of the harder primers you can reload with.