DWM Commerical breechblock question

[sheepherder]

Originally Posted by ithacaartist

This dent is puzzling, indeed.,,if the depression around this one's hole was caused by a punch...

How about if it was extensively dry fired, and the owner tried to remove the resulting 'ridge' by use of a round stone in a drill...or even a drill bit...

[ithacaartist]

Originally Posted by sheepherder

How about if it was extensively dry fired, and the owner tried to remove the resulting 'ridge' by use of a round stone in a drill...or even a drill bit...

It all looks smooth and regular, although a slightly different color than the rest of the flat surface there. I'm doubting a rotatory stone or burr..maybe a drill bit sharpened at a verrrrry shallow angle (which, itself, would be hard to center?), but a long time ago because the area does show some "age" in the pics. The base of the cone of the f.p.'s tip looks a little gnarly in the pics, how much dry firing would be necessary to achieve this?

Perhaps an experiment is in order. Pounding a sacrificial firing pin repeatedly into a sacrificial breech block would answer a lot of questions. As I understood it up until now, the damage risked by dry-firing was that the tip of the f.P. would work harden and become more brittle--enough to snap the tip off with the shock and momentum involved in the dry-fire. I'm still skeptical that a cone pounded into a cone would produce the mushrooming/upsetting around the hole.