If you are willing to plink with much reduced loads—not much more powerful than a 22 rimfire—you can use 4 grains of Hodgdon's Trail Boss with a 55 grain bullet. This subsonic load is on their web site. Trail Boss is ultra clean burning, IME. I used some in .45 ACP in a single-shot barrel as an experiment, and the fired cases came out looking new. Shiny and carbon-free brass
on the inside as well as out.
If you want a full power load for a gas operated gun, you might look at Hodgdon's CFE 223 powder. That will at least keep the copper fouling down.
Their load data site has the information.
For plinking cost, the Ramshot powders are typically most economical. The X-terminator powder should do well for you as a plinker starting at around 21.5 grains for 60 grain bullets and 22.5 grains for 55 grain bullets. Choosing Ramshot X-terminator rather than the slower burning Ramshot TAC will not get you to quite as high velocities, but will let you use a bit less per round without the pressure dropping to where the burn gets dirtier. That's why I thought of it for plinking.