currently it's .45ACP, because the brass (Federal) + primers (Winchester WLP) that I'm using never want to seat flush, so whenever I'm priming brass on my press (a single-stage Rockchucker II), I'm always pushing up on the handle like there's no tomorrow...pressing out 100 rounds this way doesn't seem very appealing...
And then the bullets I'm using (Missouri, 12bhn .452"-dia, 185gr) + the thicker brass almost always bulges the cases, so I run all the 'finished' (seated/crimped) rounds through the resizing die one more time (ugh)...Maybe I'm doing something wrong.
Or maybe I need to get a taper crimp die.