AR Striking Primer When Chambering

[heavymetalman]

I bought some mags for my Armalite AR chambered in 7.62x39 and I was function checking the new mags by manually cycling some ammo and it smelled like something was burning so I stopped and was looking for the source. I never found out for sure what it was but while I was checking everything out I was looking at the bullets that I had cycled through and I noticed that they had light primer strikes on them, some of them two strikes(cycled through more than once). This is definitely not normal right? Should I be contacting Armalite? I hope the burning smell was not one of the primers partially going off.....that could have been bad.

Image: (one strike, two strikes, not cycled)

[DefensiveCarry.com]

[C9H13NO3]

Every AR, M4, and M16 I have ever handled does that with the 5.56. I'd assume it's in the design, and would do the same with 7.62.

[mcp1810]

AR's have a free floating firing pin. When the bolt goes into battery the firing pin is moving with the bolt. When the bolt stops the pin keeps going until something stops it. No big deal.

[heavymetalman]

Oh, ok. The strikes are light enough that I wouldn't think it would set one off, but I just had to make sure. Thanks!

On another topic the CProducts magazines I got seem to be good, except they forgot to solder one of them

[QKShooter]

I think that burning smell that you smelled was totally unrelated to the task at hand.

[Guns and more]

The manual on my new Colt AR said this is normal.

[Knuckledrager]

This is normal but it is something to be aware of. Normally, the minimum firing pin indentation needed for ignition is .017" Repeated chambering of the same round can cause damage to the primer. This may change the depth of the indentation needed for ignition and the round may not fire! There have been cases of LEO guns not firing when needed due to this issue. Not re-chambering the same round is a sound practice for a defensive rifle/ammo. Once chambered, put 'em in the range bucket for training use.

[matiki]

The others posting that this is normal are correct.

There was an issue with the M-16 when it first went into production - the firing pin was heavier and they were using lighter primers that would cause "slam fires" when you release the bolt on a loaded magazine. Subsequent trial and error resulted in use of heavier primers to reduce the occurence.

You can also cut down on the potential for this issue by using the forward assist - Holding the charging the handle and closing the bolt with resistance, then confirming that it seats with the forward assist will keep the firing pin from slaming into the primer.

If you're using military loads you're not likely to run into a problem with soft primers - just be aware that as another response noted, repeatedly slaming the bolt forward onto the same round is just asking for trouble.

[Blackeagle]

Perhaps no one has mentioned this yet because it should be obvious, but make sure you keep the gun pointed in a safe direction when you chamber a round!

[Knuckledrager]

The others posting that this is normal are correct.

There was an issue with the M-16 when it first went into production - the firing pin was heavier and they were using lighter primers that would cause "slam fires" when you release the bolt on a loaded magazine. Subsequent trial and error resulted in use of heavier primers to reduce the occurence.

You can also cut down on the potential for this issue by using the forward assist - Holding the charging the handle and closing the bolt with resistance, then confirming that it seats with the forward assist will keep the firing pin from slaming into the primer.

If you're using military loads you're not likely to run into a problem with soft primers - just be aware that as another response noted, repeatedly slaming the bolt forward onto the same round is just asking for trouble.

The forward bolt assist technique may spare the primer a beating but it may cause the extractor to fail to engage the cartridge rim causing a double feed.

[matiki]

The forward bolt assist technique may spare the primer a beating but it may cause the extractor to fail to engage the cartridge rim causing a double feed.

That's what the forward assist is for.

[C9H13NO3]

You should never ride the charging handle home. Always let it go completely when chambering a round. The foward assist is for using if it doesn't go completely into battery. When you shoot, the next round is going to be chambered with the full force of the spring anyway, and it will be dimpled if ejected.