Easy to see that the numbers go from fast to slow, and I figured they might have something to do with their chemical makeup, still my trivial mind had to ask.
So, WC = Winchester Contract? Okay, makes perfect sense. They all would also be Ball(little trademark thingie goes here) powders, too?
I once stomped off/pried off a 20 mm projectile* and poured a round powder on and about the flightline. First time I'd seen round powder.
*Air Force: smaller than .50 caliber is a bullet, .50 caliber and larger is a projectile.
That brings up another trivial question: Assuming the item is a "bullet", what's with tip, head, slug, projo, etc.?