Ok, I figure this is the place to ask. It has happend twice, and with two differnt guns. I sight in my guns cleaning after every couple of shots. Get both guns shooting 1" high at 50 yards. Clean the guns well and reload them for hunting. In the first case the gun set for a week before being loaded. The first shot on a deer I miss. I take the gun back to the house and it' s shooting 12" high? I figure scope or mounts moved? 2nd gun is loaded the next morning for hunting. Shoot a turkey that evening, perfect shot placement at 40 yards. Clean the gun and reload for the next morning. Two days latter miss a shot on a HUGE 6 point. Lot' s of mass, just no brow tines. I am frustrated and go back to the house. Check guns zero, guess what it' s shooting 12" high at 50 yards! Now I am not sure what happend. It could be the scope or mounts again, but I am not so sure. I am shooting 120 grns of pyrodex with 240 grn xtp bullet in a sabot. The gun is a 50 cal t/c black diamond. The first gun was a cheaper CVA staghorn, I used the same bullets in it, but only 90 grns of pyrodex. Since then I clean well between each and every shot and have checked the mounts, rings and scope. everything seems in order. The scope is a leupold, it' s older but works great. It' s been on my 7mm Mag for years, but I wanted a better scope for the black powder gun. I guess my question is, other than the scope moving, would something else cause this to happen, such as the way the gun is cleaned, loading procedure etc? Or do you think I just happen to have some bad luck?