I will sure see if I can find some N555. Looks like a good option.
I'd still like to figure out what the deal is with these book figures... for example H1000 on the Hodgon website lists 48.2gr max for 6CM... that fills the powder right to the top of the case! And hornady doesn't even list it as an option... but at the max I can get in the case with my seating depth, I get about 2836fps (46.2gr). A smidgen better than the 2830 I get with RL16 at 41.1gr. But H4350 is listed at 41.7gr and 41.6gr on the Hodgon website and Hornady... but that leaves a lot of space left in the case... and velocities in the 2870-2890 range. Great velocities, but SD is high.
But here is what I don't get... hornady says max for 6.5Creed for RL16 is 42.1 and 41.5 for H4350, but for 6CM it's 41.1 for RL16 and 41.7 for H4350... so why a higher powder charge for RL16 with the 6.5creedmoor but lower for 6mm Creed, and the reverse for H4350??