I fired about 50 shots through my brand new 336ss yesterday. I had an extraction jam and found the spent case was split all the way around the circumference (about a quarter inch up from the primer). The casing was in two pieces. Looking at the other spent brass I see a noticeable bulge in all of them ( in the same place where the one split). Do I need to send this gun back to marlin? Doesn't seem right to me but I have limited experience here. Shooting the hornady leverevolutions.