Try H335 if you want to boost speed a little. I've got a bottle of it that I haven't even opened, but load data suggests it gets hot a bit faster. It's a canister grade equivalent of the stuff used in the M855 loading IIRC. 2206H is a great powder for .223 IMO. I run a compressed load under a 68gr Hornady match as my do it all type load.
Bookmarks