The original load developed for the 1873 SAA was 40 grains (volume) of... what, 2F or 3F? Anyway, the bullet was a 255 grain RN or flat point RN bullet. I've read 40 grains won't fit in a modern solid head case, and still maintain the specified 1.6" oal, which is about as long as a Colt cylinder will take. OK, so 40 grains will apparently fit in a balloon head case and velocity was specified at ~900 fps+. Pretty potent, even by todays standards for a .45 SAA revolver. Then, sometime between 1873 and the mid-1890's, the army specified a standardized military load consisting of 28 grains (volume) 2F or 3F, and a 230 grain RN bullet. 2 questions; #1, why? Were soldiers that intolerant of the recoil? Were the revolvers coming apart? And question #2; As bp loads can have no airspace between the powder charge and the bullet, how did munitions factories of the time solve this problem when they went to the 28 grain load? Nowdays a reloader will fill the excess space in the case with Cream of Wheat or cornmeal or some other lightweight, inert substance, but how was it done a hundred+ years ago?