I once purchased a box of silver bear ammo for my 30-06. I noticed at the bottom of the cartridge, just above the rim, was an indentation. This indentation, to give a better explanation of, was all around the cartridge(and looked like a rubber o-ring would fit in the groove, although I know its not for an o-ring). I thought nothing of the groove because It was on all of the rounds and was like that from the factory. When I shot the first round in my bolt action, it was very difficult to extract the round. When I finally ejected the cartridge, I noticed that the once indented groove had popped outward and that was causing the round to be difficult to eject. I never shot another silver bear. Does anyone know what the groove is for? Maybe certain rifles, or for belt feed? I'm just glad it didnt damage my gun. Has anyone else had this happen?

Junk ammo

Now that I look back at the situation, I dont even know why I bought the ammo in the first place. I usuall buy remington or winchester. I've recently started reloading

Haven't had this happen because I wouldn't give you $1 for a lifetime supply of that crap--2MG

I was at a friend's house tonight and we were going thru the ammo cabinent.

"Hey, what's this box of Brown Bear 9mm?"

"Its crap, wont eject, at least not from the Beretta, you can have it if you want."

I looked at it, and indeed, it also has a ring around it like you describe. And it doesn't eject either.

A magnet will stick to the bullet, it has a steel jacket to go along with the steel case. That has to be hard on a barrel.