Very nice TS. The 12x will be good to 7-800 yds on that rifle.
Dialed in for 100 yrds, it will be 4" low at 200, 15" low at 300, 32-34" low at 400, 65-70" low at 500 and 114-118" low at 600 yrds with about any bullet weight from 147 to 168 grainers
Battlesight zero [ BSZ ] is 275 yrds. If you can shoot irons with it, the BSZ will be 2 clicks up from your 200 yd setting. That will put it at 6O'clock hold for 100, stomach hold at 200, dead on [ POA/POI ] a 275, sternum hold on the chest at 300, shoulder height hold at 400 yrds without having to run the rear elevator at all in the field.
Congratulations on the new acquisition sir. Nothing says loving at distance like a 7.62x51 precision semi auto :thumsup