My Dad gave me a new Ruger Bearcat about 4 years ago. I took it out and shot at a few cans with it but recently I shot it at some paper and it keyholes with all 3 kinds of ammo I brought with me (CCI, Federal Bulk, and Winchester) Anyone else have this problem? I have several mark II's, a mark III, and two single sixes that have no problems.
It's not leaded up is it?
Nope. It's clean as a whistle.
The bore is possibly oversized or it's "choked," likely in the forcing cone, and under sizing the bullets as they pass through.
I think I will email Ruger. A google search found that this problem has happened before.