This happend all the time to this shooting location
See the photo bellow
I used swarowski range finder - multiple reading and got the same distance
The shots was at cold bore shot 4 moa at 400yrd, and the other 3 round at the same impact 4moa
Please note I used H1000 powder so no fluctuation on temperature.
Temp was 41F to 49F during shooting session., and the ammo was left on plastic case with the lead on, so no sun exposure.
3 shots, let the barel cool down, and no changes in elevation.
It sound strange but this can be the wind? the wind from the valley?
At the target and at the shooting location wind was 2-3 mph from 3 a clock.
Please note This happend all the time at 400yrd at different day, or different temperature.
I was in fall 2009, ian 12 2010, feb 4 2010, and all the time shooting at 400 yrd at the same target location (see the photo) over the small valley I get the same 4 moa elev. I know is off from 5.25Moa (JBM, Berger, Exbal) prediction, but I tried to get a logical explanation.
The fanny thing is if I go at 2200elev, on plain field and shoot at 400yrd, the 5.25 MOA match.
So by excluding one by one, I suspect the hidden wind from the valley bellow, can cause the almost 1.45 Moa difference.
Did you experience the same off value from shooting over a valley?