Yesterday I installed a wilson combat drop-in barrel in my inherited BM. I have never done this, but after watching many pros on youtube, I felt fairly confident. It went well and I was trying some rounds and after about 20 rounds had a case rupture at the bottom. It was very unsettling.
The gun seems fine except for broken grip panels and warped mag follower. I had no real injuries thank goodness.
The loads were some older ones I had given dad. I'm glad this didn't happen to him. I thought I had screwed something up but I rechecked my install and everything seems correct. At first I figured it fired out of battery, but the case was still jammed fully seated and the primer was flat and extruded. I pulled the remaining loads and all were at 5g unique. I must have double charged that one or maybe the bullet set back. I'm still shook up but reminded how serious reloading can be. Cant seem to load pics from my phone so will load some later.