An interesting part of his OP, is he states the loads he fired off had shown good accuracy "1.25" or better" on the first outing, but then states he tried them at 200 yards on a different day. I honestly don't think he is working with a good "proven" load. Things like a change in temperature can drastically effect the accuracy of a load, depending on how finicky the rifle is and what powder he's using. Again, he doesn't give specifics on the load. ...
What I actually said was that every load I tried was 1.25" or better at 100 yrds. The load I settled on after the first days testing has shot 3/4" or better at 100 every single time. And I realize that 4 or 5 groups don't really prove anything, but I feel like the rifle is showing good accuracy......probably better than I'm capable of on a regular basis. I'm just having a hard time understanding how a load that does good at 100 will be bad at 200?
I rarely get a chance to shoot at 200. When I do my guns/loads that deliver sub 1" loads almost always open up to closer to 3." I blame that on me. Your case is different. Your experience is that if you have a one inch gun at 100, then it's a two inch gun at 200. I would be inclined in this case to remove the shooter as a variable. I'd try one more scope (one with adjustable parallax if possible) if possible. It's a pita, but maybe remove a scope off of one of the guns that you get 2 inch 200 yard groups with. At that point I'd say you have eliminated the scope as a possibility. That leaves you with a gun that misbehaves.
You said it's lightly used. How often do we read here of someone who can't get a gun to behave and they "send it down the road?" You may have had a gun sent down your road. I hope you can get everything worked out. I will be following this thread with interest.
