Temp sensativity is a concern.
H4350 goes across both rounds. I see that Superformance does as well. I haven't found too much info on others using that and I'm not familiar with it. From the burn chart it is slower than either 4350 & RL17. I'm wondering about it too. I may have to buy a small canister to check out. It is supposed to be a progressive powder, but so is RL17.
According to the Hornady data, Superformance has a listing for a wide range of projectile weights even light projectiles for the 6mm. The listings for the 6.5mm cover 100g and heavier, but not the lighter ranges. Fair enough, I want to stick with 6.5's that are >= 129gr and with the 6mm I'll stay with the 103gr or 108gr projectiles. For my other rifles I usually use Hodgdon powders (H335, CFE223). Anyone have experiences they care to share about Superformance?
I have some AR-Comp. Alliant states it's not temp sensitive. Data available is kinda slim. There is some for 223, 243 & 308 (308 having a pretty good weight range) from Alliant. Nothing from Hornady. There is limited data for it in the Grendel reloading handbook. Shame because velocities that are listed don't look bad. Anyone try AR-Comp?
Oh well, one of the other things that is great about shooting and loading. Always something to lookup, research and try to understand.