Lots of cowboy shooters insist on using the .45 Colt revolvers because that was the "real cowboy gun" but they want .38 special wadcutter recoil. Loading the Long Colt down with tiny powder charges and light bullets does pose a problem. The powder gets lost in that huge case and chamber pressures are so low that the powder does not burn consistently, sometimes not at all and sometimes with disastrous detonation!
A "solution" has been proposed, that being a sort of .45 Short Colt, a cartridge with the head of a .45 Colt but the length of a .45 ACP. That greatly reduces the powder capacity and can be loaded with standard .45 ACP dies using .45 ACP data. I tried it and found it is not a "solution" but just exchanges one problem for another.
I ordered 100 cases from "Adirondack Jack's Trading Post". The price was reasonable, $25.00 with shipping included, and the brass was good quality, headstamped ".45 Cowboy Special". I loaded up 20 rounds, five each of four different powders with .45 auto rim starting loads, and went shooting. I got holes all over the place, five shot groups went six to ten inches at 25 yards.
Well I should have thought before ordering. We all know that for a revolver to shoot well the bullet must well fit the chamber throat. Using the short cases in a .45 long Colt chamber leaves more than 3/8" of empty chamber for the bullet to rattle through before it even reaches the chamber throat. The 200 grain bullets I was using have only 1/4" of bearing surface. There was no chance they would enter the throat straight and centered and thus no chance they could shoot accurately.
This would be a fine cartridge in a revolver chambered expressly for it, although a Ruger in .45 ACP would probably be even better. When fired from a .45 Colt chamber the accuracy may be good enough for the cowboy who values low recoil over accuracy, though why they can't just shoot .38's is beyond me. For a general field and plinking round I find the "cowboy special" to be totally worthless.