Quote Originally Posted by simplerider View Post
Once had some 9mm that wouldn't chamber in my pistol all the way. When I went back to my bench I measured and remeasured and found several rounds were longer than what should have been. I drove my self crazy checking differences in lot numbers and measuring chamber. Turns out my seating die had come loose in the press and backed out ever so slightly, but just enough to give that extra length.

Check your dies for any loosening. Just a thought.

Good Luck.
Measure every round after seating. No die movement. The oal measured and remained consistent. Only this time it was .030 different than last lot when contacting lands