"It's my understanding they use to sell brass a standard length, and you cut it down to 45-60,70,90 etc."
That was in the 1960s or 1970s. "Blank" brass was available from a company called Bell Extrusion Laboratories, Ltd. They provided a number of differerent basic cases that could be shortened, necked, etc. to provide cartridges for quite a few of the old black powder (and some of the early smokeless) rounds.
Here we go!
Cartridges of the World 4th edition has a rundown of BELL's offerings.
The .45 blank that they sold could be used to make:
- .45-100 Ballard
- .45-75 Ballard
- .40-60 Marlin
- .44-70 Maynard
- .40-50, .40-70, and .40-90 Sharps bottleneck
- .45-100 and .45-120 Sharps Straight
Pretty good...
Oh, and it also formed into the following Winchester Center Fire cartridges:
.33, .38-56, .38-70, .40-60, .40-65, .40-70, .40-82, .45-60, .45-70, .45-82, and .45-90.