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bo2
June 3, 2001, 08:34 AM
I bought a model 12(12 ga) that was manufactured in 1949. It's set up for trapshooting, and I've had 2 firing pins break. I don't dry fire the gun, and only use factory"AA" light target loads. Have only put 750-1000 rounds through it. Why do the pins keep breaking? Someone at another site wrote "sounds like the pin wasn't fitted properly." OK, that's alotta help! Both pins fit into the bolt just fine as far as I could tell. I assumed that they were made to a certain spec. so as to fit into the bolt without any extra "fitting" Help!

Badger Arms
June 3, 2001, 12:44 PM
Without seeing the gun, I can't diagnose your problem. I have a few suggestions. Yes, it might be that the Bolt is out of spec and the firing pin is being damaged somehow by the normal action of firing the gun. Normally, the primer cushins the fall the primer. If the pin is coming in contact with the bolt or being hit off-center, or any number of other things, it might be stressed too much.

How did the pin break? Is it a crack? Is it bent around the crack? Is the tip of the pin broke or is it broke at some point along the shaft?

Firing pins break. 1000 dry firings might certainly break one but if your gun is treating the pin as if it's dry-firing, 1000 rounds might do nearly that much damage. When you replaced the pin, did you get a used firing pin, a new OEM one, or an aftermarket one?

bo2
June 4, 2001, 08:41 PM
Thanks for the reply! I bought the gun used, so I don’t know if the 1st firing pin was original or not. The 2nd pin was from PA Gun parts, which is an obsolete parts supplier recommended by Winchester. I’m assuming that the pin was made per original specs. Both pins had a piece of the tip break off. In the case of the 2nd one, the tip appears to have stayed aligned with and inside the hole in the bolt, because examination under a magnifying glass showed a “peened” edge around the break instead of a “sharp” edge. Both the gunsmith I took it to and I think that the gun actually fired for a few rounds with the tip broken. Finally, the 2nd pin broke again, and basically broke in half. Could it be that the hole in the bolt is worn and is now too big in diameter, causing too much “play” in the pin?

Badger Arms
June 4, 2001, 08:53 PM
That the locking lug causes a lateral movement in the bolt as the gun fires thereby damaging the pin.