LR-308 Firing pin bent.

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Hello all,

I've been building a franken-308 for a long time now, and I have had nothing but problems. this rifle is quickly becoming my albatross. My most recent blunder is the firing pin bending towards the back of the pin. I am curious if anyone knows what may cause something like that. The BCG is from Faxon and is the full mass bolt carrier. I suspect my trigger for some reason which is a Geissele SSA, I also replaced the firing pin retainer with a retainer from Next level armament. any input would be nice.
 
Well, I agree. That is strange.

I honestly think it might be a firing pin that got bad heat treat (thus leaving it annealed and soft). I can't see that even a very strong hammer spring could bend a properly heat treated firing pin
 
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I am not familiar with that type cross pin that retains the firing pin.
I'm used to the small cotter pin type used on the 5.56 guns.

Could your hammer be driving the firing pin forward against this cross pin hard enough to bend it?
Remove the cross pin and check the inward throw of the firing pin into the bolt, when it's in the simulated bolt locked position with the carrier. [ Basically. Is the firing pin bottoming out as it should on the back of the bolt? Or is it hitting the firing pin retaining cross pin first?]

I think your bolt may be to short when it's locked in the breach. [Doesn't take the impact of the firing pin.]
Or the rounded head of the firing pin [The area struck by the hammer] is to thick on the inside. and contacting the cross retainer pin and being bent downward.

Or some combination of the two?

Also what is the relationship of the hammer to the firing pin?
Pictures of the lower with trigger group?
 
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OP
Coolhandluke
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I will post more pictures, but I want to provide more information. I dry fired this thing a time or three and that's when I noticed that the pin was bent.
 

v0lcom13sn0w

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i would say get another firing pin and see if it freely floats in the bore. that one looks like there is a burr in the middle lug that may have hung up in the bore.

if the new one free floats i would say run it and you probably had a bad firing pin. im smellin what @IronMonster is steppin in and thinkin he probably nailed it on the head.
 
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Hello all,

I've been building a franken-308 for a long time now, and I have had nothing but problems. this rifle is quickly becoming my albatross. My most recent blunder is the firing pin bending towards the back of the pin. I am curious if anyone knows what may cause something like that. The BCG is from Faxon and is the full mass bolt carrier. I suspect my trigger for some reason which is a Geissele SSA, I also replaced the firing pin retainer with a retainer from Next level armament. any input would be nice.
The firing pin is pretty well protected in the assembly.
So I think you said all you did was dry fire it a couple of times ?

If the firing pin was in a position too far to the rear, the hammer could strike it in an upward motion instead of flush on the end of the pin like it is supposed to. (was there an aftermarket part/pin involved here ?)
I could see a few upward strikes bending the pin like that.
Check to make sure that your firing pin has full, unimpeded travel.

Crappy AR15 animation but you can at least see where the firing pin would be vulnernable if it was sticking to far to the rear...

Edit:
Is it possible that the retaining pin was put in the wrong position so as to impede forward travel of the firing pin ?
 
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