I have an Evans and Lone Gunman does too. He's used his for at least one stage in a match. There is an Evans 44 short and a Long. Buffalo Arms has brass and reloading dies. Bullets are another matter, as production tolerances weren't great and groove diameters tend to fluctuate a lot, got to slug the barrel.
The 28 round rotary mag (the wests first assault rifle) would be a pain at matches because you'd have to load ten rounds, then cycle the action 18 times to get the first one up the shoot.
There are several kinds of brass that can be used to make 44 Evans, I hope to get some rounds together someday.