I don't have a Hawkeye.... my .223 is a bull-barrel Savage M12.
However, after a few years worth of reloading and a few thousand rounds downrange, I can give you a couple things to think about....
First and foremost.... what's the twist in your rifle? 1:8 generally works best with something around 70 grains, 1:9 about 60 grains, 1:10 for 50-55 grains, and 1:12 works best for 40 grain bullets.
Flat base bullets generally group better than boattails at shorter ranges (100 yards or so), but the VLD and boattail designs will win out at 200+ yards..... and, as a bonus, they retain velocity better, and therefore shoot flatter and carry more energy at longer ranges.
I've found that extruded powders generally give more consistent results than spherical powders in the .223. Settled on Reloder 15 as the go-to powder for 60 and 69 grain loads... Reloder 10X for the 35 and 40 grain screamers.
You will almost always find that the most accurate load is a little less than the maximum load listed for the particular combination you're loading. Shoot 5-shot groups (not 3-shot groups) with loads about .50 grains apart, working from 10% below max. Stick with the one that shoots the tightest group... I'll bet it's 1/2 grain below max.... maybe even 1 grain down. If you have a Chronograph, you'll also usually find the most consistent velocities at a slightly below max load - and you'll also notice that they are not a heck of a lot slower than the max load.
