I've been reloading for at least 15 years and I've never had a problem with any reloads in any pistol except Glock. I've owned three Glocks and all have locked up tight on my reloads with a failure to go into battery. No other pistol brand has been a problem. So are Glock chambers tighter? I used to use a Lee FCD thinking it would help with this issue. But when I measured a reloaded case with and without the FCD there wasn't any size difference. So I quite using the FCD. But today my new Glock 19 locked on a round that wouldn't fully chamber. I think I'm done with Glocks unless someone can tell me what I'm doing wrong.