Originally Posted by skires
I reckon you get the guides fitting well. You keep petrol based lubes off the seal ( use dry graphite ). Matt's convinced of that and Tony. As little as possible lube on the spring. Get the seal fitting as loose as possible ... or use O rings. Try and zero at the same rate of fire, and at the same temp, that you want the damn thing to shoot accurately at ... and the shift will be minimal.
I'm going to add to that list balance of rifle and butt angled at 90 degrees to barrel as it sits in shoulder. A poorly balanced rifle or an angled butt ( usually top further back than bottom ) will exaggerate muzzle vertical movement. We want that muzzle moving backward and forward ... not bouncing up and down. That pellet is released with that muzzle on the move.