[southernman]

I tried most powders I could get my hands on, in Canada,
H4198, 4227, littlegun, blackout, H110, and N120, would have liked to try1680, but wasn't aviable.
N120 gave by far the most consistent accuracy, but speed at 3300-3400
N120 metres very uniformly, and thus easy to load consistently.
Little gun was the most erratic, with spreads of 500 fps, and the odd blowern primer, I wouldn't recommend looking at other powder options.
H110 and 4227 good accuracy but slow, 3200 ish
H4198 and CFE black out, both very accurate, in both my CZ rifles, but blackout giving a 300 fps over H4198 and easier to get in to case.
I up up over ten loads on sum brass, annealed at six firings. One trim, no brass loss another than ejecting them into the grass, (wish they came in neon orange ) they flippen dissapear in dry dead grass.
Have not noticed, any real amount of copper build up, with N120, H4198 or blackout, I clean with wipeout every 500 odd rounds, and normal oil/solvent every outing. Haven't seen any real amount of blue on a patch yet.
Plenty of carbon at times.