EXCELLENT advice from friend SUNRAY.
Stashing away BRASS whenever you can get it into your hot little mitts always makes sense. If you pick up an old Kropatschek you will find that even empties are $3 or $4 apiece. But if you have a supply of that nice Partizan 8mm Lebel..... and a lathe..... 2 minutes per cartridge will give you a short-neck Krop casing for about 70 cents...... and it is brand-NEW.
Ally-samey thing, 7.62x54R can be converted to 8x56R or to 8x50R Austrian, that .30-'06 and .270 the guys leave on the range makes into 8x57, 7x57, .220 Swift makes into Carcano, Jap and Mannlicher-Schoenauer when you can't buy the stuff..... and even .308 CAN be repurposed to a 7.65 Argentine.... or for that EM-2 that Grandpa stashed away.
If you are going to be in this Milsurp racket, NEVER lose an opportunity to stash away oddball casings and dies. You just might NEED it..... right after the next gun show!