I'm with Eldeguello on this one. He beat me to it. You should not have been that far off to begin with. You should have had it boresighted before you started sighting it in. I always try to get mounts that can be adjusted for windage. This way I can bore sight my scopes and have them pretty darn close before I start firing live rounds through them.

I had a buddy do this with his 870 slug gun. He threw a scope on it and went out to sight it in. He had to adjust it so much he actually ruined the scope (it can be done). He came over to my house to see what I thought and I told him the scope was toast pretty much, but he might be able to send it in and get it fixed.

I loaned him a scope and bore sighted for him real quick in my back yard. No fancy tools or anything, just looked down the barrel at a target with it in a rest and made a few adjustment. I had to shim the mounts and file some metal off the sides. I don't think the cantilever mount was very true to the barrel to be honest. We took it out a week later and it was only off 2 inches at 50 yards on the first shot. He was rather impressed.

Most gun shops will do this service fairly cheap. Even if it costs more than you think it should when you factor in the price of a scope and ammo for a centerfire it is usually worth it in the long run.

Paul