I would save myself a lot of grief and get Nick at Metrics Unlimited to send you a carrierless plug for that rifle. Then, I'd shoot cast bullets in it. I never really understood sabots.......why reduce a .50 cal. to a .45 cal.
Just never made sense to me and the cast bullets shoot very well, and have more penetration and expansion when they get there, and cost less..........getting there sometimes takes a bit of waiting...they're usually big, slow and heavy, but they bang flop deer. The last one I shot with the Huntsman was with a 470 gr. T/C Maxi Hunter at only 60 yards. I hit him center of the chest and the bullet exited his right ham. It threw him completely over backward, dead in his tracks.
Pete