45/70will expand! I went to the range to try out some hog loads and dug one out of the berm that had expanded from .439 nose to .883 the base went from .459 to .465 all the groves were compressed and almost non existent. I know sand is a bad medium but that is all I have. The alloy was aprox Lyman #2 using bees wax and lithium grease. 1300 fps + or - a few fps.