22 LR in wood stocks.
If the forearm is touching the barrel (not free floated) , change in wood moisture can and does change the pressure on the barrel. This moves the bore, while the scope is fixed to the receiver.
The biggest change in the point of impact, would be the 22 types that have 1 action screw. The Marlin M60 is the worst i have encountered. Take the barreled receiver out of the wood stock to clean, on the next trip to the range, it will need to be sighted in again. The torque/pressure on the action screw changes with the weather, also.
Even the super accurate Remington M581 with its 1 action screw will do it, but not as bad. The fix here is a modification. A 2nd action screw is added in the tang area. Then free float the barrel. Or if lazy like me, glass bed the action and the pressure point on the barrel. Seal the wood well.
Ammo- Difference in the lube on 22 lr ammo, can change the point of impact on target, but mostly when switching ammo brands without cleaning. This can be as much as 3" difference at 50 yards. So when testing different brands of ammo, clean the barrel before testing the next brand. Or shoot 10 rounds to recondition the barrel with the new lube.
Yes, it may be the scope. Most have a spring pushing against the tube inside. The adjustments on cheap scopes, is not good.
I suggest a Bushnell scope as a replacement. But both brands are part of the Vista Outdoor family. So may not make a difference??
