Posted 1/3/2019 15:54 (#7217772 - in reply to #7217746) Subject: RE: Why do my revolver shots look like this? (Pics)
Those are what we call "keyholes". Caused by a projectile that has lost stability, and yes, it's tumbling. There are generally two causes.
1. As stated earlier, the weight/spin rate/ and speed are mismatched.
2 The barrel is too large for the projectile.