I would also harden thm a little, as I have shot only pure lead out of my .54 cal, (no sabot) and I feel they expand too much, limiting penetration. This is with a 450 gr. solid lead slug. I would guess your saboted bullet will be going even faster, and will likely mushroom out like a silver dollar in the first few inches. My .54's look like half dollars, and I bet they won't penetrate well. Good luck.