I pick up a DPMS 24" 308 upper, was having light firing pin strikes on several rounds that would fire on the second try. When I got home took the bolt & carrier out to look at the firing pin it all look good. Tell I was taking it apart took out the pin retainer & the pin didn't fall out, so I pushed down on the cam pin it did not fall out & worked the bolt in & out & out came the firing pin. The whole time I was thinking it got some crap in it. Wiped it all off & there was two shinny spots on the firing pin at the tip where it rides in the bolt & where it rides in the cam pin, was still thinking crap was in there. Put the firing pin in the bolt it worked freely, then I put the cam pin in the bolt the firing pin didn't work as freely, Then I pushed down on the cam pin & it lock the firing pin. As I pulled the firing pin while pushing down on the cam pin the tip of the firing pin would pop out of the bolt pin hole & could not push it back in with out letting up on the cam pin. I'm thinking now what is the firing pin hole in the bolt off center. I pulled the firing pin out & while pushing down on the cam pin it would not go back in, let up on the cam pin & it would go right in.
This is what I found the Bottom of the hole for the cam pin is staked to keep the cam pin from going down to far, but if it's just close the cam pin can be or was forced down on the firing pin, causing drag at the bolt hole & the cam pin hole causing the light strikes. This could also cause bolt pin hole to wear as well the firing pin. I restaked the bottom of the cam pin hole so the firing pin hole in the cam pin could not go below center of the firing pin. Now the firing pin works freely, even pushing down hard on the cam pin.
I'll see if this fixed the light strikes.
This is what I found the Bottom of the hole for the cam pin is staked to keep the cam pin from going down to far, but if it's just close the cam pin can be or was forced down on the firing pin, causing drag at the bolt hole & the cam pin hole causing the light strikes. This could also cause bolt pin hole to wear as well the firing pin. I restaked the bottom of the cam pin hole so the firing pin hole in the cam pin could not go below center of the firing pin. Now the firing pin works freely, even pushing down hard on the cam pin.
I'll see if this fixed the light strikes.
