375 chey tac bullets for rum

i have a 375 rum and do mid range shooting between 200 and 600 yds i use 235 gr tsx with 85.55 gr imr 4064 in a 700 bdl 28 in barrel with muzzel brake overall is 30 1/16 in very hot and worked up dont duplicate reduce then work up i was wondering if anybody has used the bullets designed for the chey tac in a rum and also does anyboby know about the velocity of my hot load thanks for all replies