Butler Creek used to make very quality caps. They have slipped over the last couple years leading to a lot of complaints.
Interested in hearing what other people are using and happy with as well.
AR15 with Spikes tactical T2 buffer not cycling reloads un-suppressed
Point is switching to a "regular carbine" buffer isn't any different that the T2 he is running.
He may want to diagnose and if trying another bugger try a T1.