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Yes 2206H will get you into the 3200's with 55's a 22" barrel . . . .

oops - I had my Ruger models mixed up, yes with a 22" barrel it will be pretty respectable, maybe 2900 fps, and that will do for most things you'd want to ping with a 223

A case full of 2208 (about 24.5 to 25.0 grains) behind a Sierra 65 Gn will be about as good as you'll get with 2208 (its a bit slow for 223 unless using very heavy projectiles). It'll be kinda slow...