Originally Posted by blacklab
has any body tried a bog std gun without any tweeking, many years ago when the vulcan appeared with the ptfe piston seal, they were prone to temp shifting, hw80,s were best by sizing the std seal, ptfe was,nt good in them either.
My TX is pretty much bog standard - standard seal, not sized other than shooting lots of pellets through, standard spring, light lube job, delrin top hat and guide.
Not had any shifts on POI even though I have a custom stock. I did have a massive POI shift, but discovered that was a result of not tightening up my scope rail sufficiently
I'm down on muzzle velocity by between 5 and 15 fps with unweighed pellets on chrono's of unknown accuracy in this heat, and despite that I was shooting around 1/2 inch high at 55 yards yesterday at the GP. My guess is that's down to air density and probably also affected PCP shooters too. I just knocked 4 clicks off my turret and got on with my day.