I'd be worried with the tapered nose inverted in the sabot that the edges around the base of the sabot might cave in (wrap up around the nose) under pressure, disrupting the skirt seal...then accuracy / velocity / consistency might suffer...dunno.

I did take a couple of deer using .452/255grn lead semi-wadcutters in an MK85 & black plastic sabots years ago...they were hard cast lead alloy bullets that I used in a .45 Long Colt and didn't appear to have expanded any as they made a small simple straight wound channel through the heart/lung area and ultimately did the job.

I switched to Hornady .452/300grn XTP Mags after that which I found to be outstanding on deer, expanding to the size of a quarter, etc...looked exactly like Hornady's catalog photos of them...took deer from 50-165 yards with them.