The grand old 30/40 Krag , aka , 30 US Army is one of my favorite rounds. I'd love to have a Winchester 1895 lever. The round is almost obsolete these days , and very under-rated. But back around the turn of the century , it was THE round till the 30-06 took over. IIRC , till just recently , the long standing Boone & Crockett record elk was taken with a 30/40 Krag.
My 30/40 shooting and loading is limited to original US Krag rifles and carbines. Local gun shop was liquidating a deceased shooters collection and I got 10 boxes of Hornady 220gr RNs for $10 a box . They will be loaded over 40.5grs of IMR 4350 , approximating the original US issue ammo.
Awhile ago , I picked up a bag of 100pcs nickeled Remington brass. Should look spiffy in my original Mills cartridge belt. Most of the original US Krag and 45/70 ammo destined for the Phillipines , Cuba and other damp climates had tinned cases.