Bottom line on splash backs, try like heck to avoid big bones (shoulder, spine and then on a frontal the breast bone) and if I was really wanting the pelts intact I'd pass on the frontal and try to wait him out till he turns a bit.
Plus I'd go to a bit stouter bullet, the 55 Horn w/c, 63 Sierra and the 60 Horn HP come first to mind to me.
Now if the ranges were close (mainly sub 300) then I'd do some work with the 50 TNT and the 40 NBT and see how they shot and to what speed I could hold them together during their flight down range.