No marks anywhere indicating it was rechambered and I'mI haven't measured the firing pin protrusion at all.. I have an end micrometer and can do that. I did notice that at first the pin was out about 1/8th of an inch and the second time there was no protrusion... the third time I reassembled it trying to follow the directions from the YouTube video the firing pin protrusion was just barely poking out... maybe 1/32".
I'm still looking for a good six or eight picture outline I saw a couple of days ago on assembling the two screw in parts but haven't found it. Of all the damn stuff I copy and print and i didn't do that one... heavy sigh. pretty sure it wasn't re-barreled because the year, the Modelo, and the Berlin, Germanyicon all look old and authentic. I haven't researched any of the proof marks yet.
Would it hurt anything if I put an empty primed .308 case in just to test fire it that way?
George

Quote Originally Posted by usabaker View Post
How did you measure how far the firing pin extends out from the face of the bolt?

If you are not sure about the caliber, you should refrain from attempting to fire the rifle until you know. Normally a gunsmith would stamp the barrel (sometimes the receiver) with the new caliber if the rifle was rechambered or re-barreled. The only way to know for sure is to profile the barrel chamber by using cerrosafe chamber casting alloy. You can get the cerrosafe on Brownells.