I just replace my factory barrel with a criterion varmint barrel and the NSS recoil lug and my rifle is shooting about 6 inches high at 100yds. ???

I tried to keep the scope alignment as close to the pre-barrel swap conditions and I am using the same rings mounts and scope. I cannot adjust the scope elevation knob enough to compensate. I did notice that the receiver may be sitting a little higher in the rear than it used to. Could it be because of the added thickness of the NSS lug vs the factory lug? Anyone else have this happen?

The rifle is a savage model 12 thumbhole varmint in .223. The new barrel is a criterion varmint barrel in the same caliber, 1 in 9 twist.

Any help is appreciated