Schoolboy,
I just sold my Optima,but it shot 300grXTP .452 with a black Harvestor sabot very well out to 100 yds,using 100 gr 777ffg.Swab between shots for best accuracy and loading.These are tight fitting bullets,and 777 does leave crud in the barrel.I also had good accuracy with 80gr of 777 and a 385gr great plains conical,but never shot much past 75 yds.all ML's are different,but these guys here will put you close until you find out what your rifle likes best. Good luck-good shooting.

Charlie