Tales from a couple of gunsmiths

The shotgun the owner had added some weight to the butt of to help deal with recoil. He put shot in the stock bolt hole. Mixed with glue.

The Colt Model M with the funny-looking recoil spring plug. It was funny-looking because someone had used a lead bullet, apparently after losing the original.

The Glock that fell out of an officer's holster during a chase and fight with a guy. Couldn't find it in the field that night, so came back the next day. And found the pistol with a well-gnawed grip, all the way around("It almost looked textured it was so even.")

The lady who brought in a rifle & shotgun, well-rusted from sitting next to the water heater for a long time. Cleaned up and parkerized, returned to her with the advice that they needed to be kept in a dry place. She came back about two months later with both rusty, demanding they be redone.
"Where did you keep them?"
"Same as before, in the closet with the water heater."
"Did you not hear or understand when I told you they had to be kept in a DRY place?"
She did not leave happy.

And the recoil reducer he found in a shotgun stock: thin-wall pipe, a steel slug of about a pound, and a spring. Whoever it was had rolled one end so a washer would close the end, put in the weight and spring, then another washer compressing the spring a bit, then rolled that end enough to hold. He didn't test-fire it with that in place, unfortunately; I'm still wondering how well it worked.

And the pistol that came in for refinishing: a few small pits that should clean up nicely. Except as he worked the slide to smooth it, the pits never went away. Turned out someone in the past had filled in some fairly nasty pitting with something(he never did figure out what) and blued it; the stuff had taken the color well enough that it just looked like a few small pits. The smith wound up parkerizing it for the guy.