Ever hear of winchester silver tips? Prety sure they had an aluminium jacket. Also, look at the paper patching forum, Veral and others have patched bullets with aluminium foil. Shouldn't have any adverse effects on the barrel, although I, too, suspect galling, or whatever you want to call it.
Remember that energy is velocity squared, times weight, so you could get a tremendous wound from a n aluminium bullet as long as the speed held up.U.S.Military did some experimental, and some production loads with Flachettes, or tiny steel darts in the sixties. They made very nasty wounds because of their ultra hig velocity.
Shrapnel wounds are also sometimes all out of proportion to the size of the projectilebecause of speed. The whole argument was what gave people the mistaken impression that speed is the more important factor.
Also, A 22-250 or a 220 swift will penetrate steel plate better than a 30-06 with a p loads. Again, speed. I wouldn't want to cause anyone to do anything Illegal, but a truncated cone aluminium bullet at 5-6000 feet per second would probably penetrate quite a bit of steel.
