1898 Krag Loads

[ssgross]

My Sierra manual (edition VI), for 220gr RN, lists IMR4350 @ 42.3gr as its accuracy load producing 2000fps. Since I have plenty of both, I was going to give it a go.

My usual Krag load is 32.7gr IMR4064 (in abundance on my shelf), again with 220gr RN (The Hornady one, also in abundance on the shelf). The hornady manual says 1800FPS, and my LabRadar shows 1790, with SD 12.3 and extreme spread of 56. My notebook says 24 shot string, all but 3 in the 9 ring, SR-1 target at 100yds. Not bad, but it was the first load I tried and I never bothered messing with it, until now. I go through phases each year, and I'm on my Krag phase now and was just reviewing, wondering if we can do better.

So go for it right? Not so fast. Sierra's accuracy load 42.3@2000 is not their max load, but it's significantly more than Hornady's max load.
Hornady Max Load: 40.5gr @ 2000fps
Sierra Max: 44.4@ 2100, Accuracy load 42.3@2000

I'm not interested in going over 2000fps, but a 1.8gr difference in the 2 books for my target max velocity makes me skeptical, and 3.9gr difference in max load even more skeptical. If anyone has any range data on this combination (IMR4350 and 220gr RN), I'd like to hear it. Otherwise I'll start at, say, 37.5 (1800 in Hornady's manual) and sneak up to Sierra's 42.3 and see how that goes.