I carry a post lock 638 on a regular basis. Several hundred standard pressure and +p loads through mine and I've never experienced a problem.

The only problem I've EVER had was with Hornady critical defense ammo. The little rubber tip stuck out of the front of the cylinder and rubbed on the frame. It was so tight, it prevented the cylinder from turning when trying to fire DA.

I shot them up by loading one cartridge at a time.