My model 25T in .223 shoots tight groups, but it will not hold zero from one shooting session to the next. The elevation stays spot on, but windage typically changes from 1-3 inches at 100 yards.

I'll get it sighted in, go home, and the next day it will be shooting off to one side or the other.

I've tried various fixes... At first I suspected the scope, so I put another scope on that had worked well on one of my magnum rifles. No change.

Then I tried different rings, removed the savage bases and re-installed them with thread-locker and a torque driver to 20 inch-pounds.

Then I bought a new Nikon Prostaff P223 4-12x40, Leupold vertically split rings, and a picatinny rail. All torqued down to specs with blue thread-locker.

Then I glass-bedded the action. - Still no change.

Now I'm thinking that the barrel (press fit and with two pins) must be moving somehow. - I can't for the life of me figure out how else it could still be unable to hold zero horizontally.

Short of glass-bedding the barrel, do any other fixes or possible sources of the problem come to mind? The really frustrating thing about it is that the rifle shoots tiny groups, it is quite accurate.

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