Congrats for being able to face and get rid of the nightmare!Just to let you know..As a Brazilian, unable to associate coins with American personalities' names, I was free to thought the profile could even be yours; looking to the 30 shots group, a kind of being proud and relieved. Btw, dealing with inconsistent springers, some times we need some help from God
Well my problem has returned So today I swapped scopes and it didn't help the problem.Today was hottest day so far in Alabama, and I am starting to think it is temperature related.Bringing gun out of AC house into 90 degree weather.Seems as gun starts to warm up POI drops. More experiments to come.
Well it sure seems to be temp related. And that's no surprise because spring rifles are known to be temp sensitive to a degree. But IMO it should be a very small degree unless something is a little out of whack. The most temp sensitive guns I've had happened to have a couple things in common out of these factors:Tight piston seal Too much lube on the PistonToo much spring tar on the springVery tight spring guidesVery dirty barrelTight chokeI live in North AL, where the temp swings wide and the humidity is always nuts. My most temp stable rifle is my 25mm HW77K with a oring piston cap and krytox lube. The spring runs on a barely snug delrin guide with the tiniest bit of plain wheel bearing grease on the OD of the spring. The piston has a liner made from Teflon sheet and this keeps the lubes from moving and mixing. If this gun moves the POI at all from temperature, I haven't been able to tell. It's always very consistent. I actually grab it to take care of a pest in the yard over my PCPs. It hits where I aim the first shot. But it took a lot of work to get it there!I also have an old R10 that I shoot fairly often. It runs a new style HW factory seal which fits just right and is lubed with moly paste. Spring runs on a fairly loose guide and has a very thin coat of spring tar. Shoots 14fpe with a hint of buzz after the shot. It may hit 1/2 inch low at 25 yards for the first 3 shots or so, then it's right on the money for the rest of the shooting session. From a 50 degree day to the next 75 degree day, it may move the poi 1/2 inch. What you are experiencing seems rather extreme to me. It still seems like it would show a huge drop in velocity but as you noted it doesn't. If it were my gun id tear it down and see how everything was fitting and how it was lubed. Scopes can also experience temp shift like the rifle does. I've seen guys at a FT shoot make extra efforts to keep their guns in the shade and even put a towel over the scope to keep it cool. Maybe try swapping brand/make/model scopes and leave it on there for a while and see if it's any better. Since exercising the turrets earlier seemed to help, you may be on to something there. Hope you get it sorted out. Shifty guns are a pain in the butt
Maybe you could add some data to the Alabama science, just trying to have some food for thought.. By now, what is occurring to me would be:- at each of the temperature extremes (when the difference is relevant), you could go to the chrony and see what happens with fps; - and, directly from the AC to the sun, you could do two experiments, treating the rifle and the scope separately.. before shooting; rifle protected and scope/mount exposed; scope/mount protected and rifle exposed;