I have several recent build AR15s that I would like to accuracy test. I have a scope that I use for load development, and I'm going to put it in a DNZ Reaper mount. The ARs have different barrels, and are configured differently in terms of rails etc. But the uppers are identical. I don't want to have to bore sight each upper and spend a few rounds zero'ing them -- I'd like to zero one upper, shoot it, and then move the scope to the next upper (the lower will stay the same throughout the test, so cheek weld and position will be the same, along with fire controls, etc) and repeat.
Of course I realize my zero won't be 100% on, but I'm going for group size and muzzle velocity data. As long as I can hit a 8x11 sheet of paper at 100y so I can print the groups, I'm fine with it.
So the question is, assuming geometry on the upper receivers' rails is the same, can I expect a scope that is shared across a couple of uppers for an afternoon of testing to be able to produce hits that are "close enough?"