I just bought my first Benelli an M1 super 90. I am having problems with it jaming some times. The stock is to long for me and I dont get the gun tight to my shoulder sometimes. I was told this is why it jams, my question is can i shorten a synthetic stock and how? I put a plastic Benelli but plate on and the gun fits much better but the recoil is pretty harsh. Any advice woul be wonderful.