OP has been seeing some low left strikes relatively consistently from week to week, and relatively scaling with distance from 100 - 300. It's not occurring for ALL groups, as it would if it were a zero offset error or for consistent wind errors, and he's shooting some of his competition targets as round robin, some as sequential shot groups, so it's kinda odd.
The OP and I have already discussed excessive grip pressure, trigger management, and excessive shoulder or cheekweld input against the stock (shooter errors which either pull the pistol grip outward or push the buttstock outward). We also discussed wind, since he's shooting on the same range at the same direction - but the varying shot sequence format and relatively inconsistent response doesn't really seem to fit wind - and the direction isn't really consistent with wind rose response.
@JFrank - of note, he's striking low LEFT, down and out almost on a 45* line, so the wind rose doesn't really explain his offsets (whereas a ~10 o'clock wind WOULD explain low RIGHT groups).
This wind chart is dedicated to barrels with a right hand twist and wind from a single direction. The arrow indicates direction while the circle is the point of impact. These are generalizations and subject to wind speed as well. ( meaning you could get blown off paper in the wind is strong enough)
