Guys,

Was shooting my L4 today and have some primers I am concerned about. Ammo used was factory Lake City 7.62x51 nato stuff. I am not getting flattened primers, but it does look like I am on the very verge of piercing the primers. Looks like there is a sheared bit of metal corresponding to the firing pin geometry that just hasn't liberated itself yet. Firing pin protrusion is 0.050" (1.27mm). It would seem to be a bit great in light of a rule of thumb I have read that one doesn't want to have firing pin protrusion much in excess of 1/2 the pin diameter which I'm using the narrow section of 0.078"..so it's ~0.015" greater than that.

Narrow section of pin to bolt channel clearance is ~0.003-0.004".

Something to bear in mind is that the semi firing pins are heavier on account of the length to get to the striker. Not sure how hard the striker is hitting it in comparison to the carriage post thingy in a full auto gun.

Anyhow, was going to start working the pin protrusion down until more normal primer conditions prevail.

Please let me know what you guys think, thank you in advance for any help...
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