Aluminum rings work great on heavily-recoiling pistols if they are correctly installed - and if you use three of them. SSK used the aluminum Bushnell rings on Weaver-type bases for many many years on .45-70s and heavier recoiling XPs without problems. I used them too, on .35 Remingtons, 10" .45LCs and .45-70s without problems. Unfortunately, Bushnell stopped makng them, now SSK uses the aluminum Leupold etc. Rifleman rings. They are not the quality of the Bushnells, but using 3 or 4 will solve the problem.
Note that the rings must be correctly installed. They must be pushed forward as they are tightened so the cross bolts bear against the mount crosscut - each ring. Tighten firmly and use a strip of 400-grit paper between the ring and scope. Do it this way and your problems are over.
For deer loads, try any 300 HP ahead of AA2015. Work up and do not exceed listed maximums for weak .45-70s. This powder works very well for me in both accuracy and velocity, 14" and 16" tubes.
