AR15 light primer strikes

[Vigilant]

Gunsmith said it was the gas block. I guess one of the set screws was loose? Going to go shoot it to see if its running right now.

It's good that he caught the loose set screw, but that should have nothing to do with a light primer strike?

ETA: its already been said.

 

[Gabriel]

Possibly a tolerance stacking issue where the firing pin is barely extending far enough to set off any of the rounds and any primers that are set a bit deeper aren't getting ignited. They make a gauge for that, but trying a different bolt would do it also.

 

[Vigilant]

Any updates?

 

[Hohn]

Sounds be me like headspacing, given the barrel replacement. If the barrel extension wasn't properly fit to the barrel, this is the likely source of a problem.

The lower is two years old. The only parts swapping have been buffer parts, which can't cause light strikes. And there's no reason to think of a trigger spring or hammer spring suddenly getting weak--those are progressive failures.

Logic to me says you can rule out the lower for now. Upper, however, is completely brand new and totally not proven at all.

Take off the upper. Make sure BCG can go fully into battery. Check headspace. Either the bolt isn't going all the way into battery or when it's in battery the headspace is excessive.


The problem isn't likely a "light" primer strike, it's a "shallow" primer strike. They resemble each other, but aren't the same thing. In a light strike, the primer doesn't ignite because the pin doesn't hit the cup *hard* enough, while with the latter, the primer fails to ignite because the pin doesn't travel FAR enough.

 

[rugertoter]

What about the internals of your BCG being fouled with carbon build up?