Anyone ever try this. It seems like it has potential for nice reduced loads.

Never tried it myself, but a lot of Cowboy shooters do it, and the Army used them for years. When both Colts and S&Ws were in use, the obvious solution to the "2 kinds of ammo" problem was to use Schofields in both. The Army had gone to loading down the "long Colt" round with filler wads anyway, as the Colts (and a lot of the troopers) wouldn't stand up to a steady diet of full house loads, so there was no significant power difference.