when trying to seat a bullet. Note the ring at the tip of the ball point pen. It extends 360 degrees around the bullet. What's happening is the bullet is hitting a choke point in the too small throat and is pushed back in to the case and being engraved by that part of the throat. Higher neck tension, enough to prevent bullet setback, won't allow me to close the bolt, other than with a 5 lb. sledge hammer.

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