I have a real problem with my reloads keyholing. I am completely stumped. Help. I have not had a problem until a week ago, my loads have been fine until then. I am working a steel load for my open gun. I am shooting 9mm, 124 gr montana gold bullets, loaded out to 1.155", 6gr HS-6 powder, crimp about .376-.377. It was shooting fine until a week ago when I overcrimped about 100 rounds and discovered the keyholing. I set the crimp back to where it is now but I am still having a problem. It shoots winchester white box flawlessley but not my reloads. The barrel is a schumann, new, .355. The bullets are .355 Any idead at all, anyone, thanks for your input.
