[blackop555]

I just shot 50 rounds of federal 40 s&w 180 grain fmj bullet. 2 of the casings I picked up off the ground were crimped in at the top in 2 places

could anyone tell me what caused this and if it has anything to do with gun. Glock 23

 

[blackop555]

Also when lining up the firing pin marks. They are in exact same spots at the bottom. Even if the extractor is loosingtension what is causing the crimp. This started happening after 150 rounds fired the casing is fine then in last 20 rounds 2 happened just like this and some cases are rubbing