Is the stock exerting pressure onto the barrel, or even the receiver?
Not that I can tell. Though with the bipod the flex in the forend is more obvious. When I fire, the rifle kicks sideways which isn't in itself uncommon just that I wonder if in that instant there's enough flex that the stock contacts the barrel.
don't know man so many variables ........and like John I'm thinking your stock cant be connected to your barrel in a way that preloading a bipod would affect the barrel or even the receiver .
Now if the stock is naturally putting a funky pressure on your barrel and you zro with that pressure, then you remove the pressure by prloading the bipod.......maybe then
sounds like you need some side by side comparison
I know my bipod doesn't effect my barrel, yet I shoot better from a bagged gun no matter how I preload the bipod .....or dont
I shoot better prone vs seated
Are you doing anything to support the butt ?
any other even slight variables you can think of
I put my support hand under the butt when I shoot whether seated or prone. It's worked fairly well for me and I still use my backpack to some degree to help support the butt too. As you suggest with the side by side, I'll reset back to how we had been shooting before the bipod.
I've also wrapped the whole thing with burlap and twine. I'll remove the variables one at a time and see what clicks.