I'm going to order a firing pin return spring for my little

.380 Kahr. I bought it used and the smearing of the primer indentations is a tell-tale of a sacked firing pin spring. It can also effect feeding. The action is unlocking with the pin still protruding. I'm certain it's hard on the pin too.

They say to allow a break in period of some 200 rnds. So buying a clean previous "tested" used gun saves you some ammo and time. A spring kit is only a few bucks. My 1911 exhibited this once and a spring kit fixed it right up.