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.

[bob q]

The first mistake for military rifle shooting for accuracy is trying to duplicate military loads . The 220 load for the Krag was pick for pine board penetration , not accuracy . Another problem is velocity vs pressure . The original ammo was a .306 dia bullet in a barrel with groove size from .309 to .311 ,it was a bore rider to boost velocity and keep pressure down by less friction . So trying to match original velocity with modern bullets can cause pressure problems . Also I have fired several dates and lots of original military ammo and the velocity was about 100 fps lees than claimed . In matches I have used several 98 and a 96 Krag with a 130 grain bullet to get .09 to 1.2 inch 5-shot groups at 100 yards. Several other shooters tried my load with similar results . Also some good groups were shot with 150's and 168's . All shot much better than any 220 load . So much fore their accuracy loads .

[ssgross]

The 220 load for the Krag was pick for pine board penetration , not accuracy .

Thanks, Bob - that's good information. I have a copy of the original drop chart (spans several pages) of the original load.
My target of 2000fps or thereabouts was not because of trying to duplicate the original load. I chose it because the Sierra manual claimed it to be the most accurate from their tests with their 220gr soft point round nose. I have a lot of them to shoot after cleaning out at an estate sale of an avid shooter/reloader. I'm certain you are right about your 130gr bullet.
I did try some 168's a while back. They fed fine in one rifle, but not at all in the other. I know exactly why/where/how it failed (not the side plate, but the area just ahead), but I'm not about to grind away or weld on material to alter the geometry of an original to make it work for something it wasn't designed for. Sure single loading is fine, but doesn't work during rapid fire. I'm off topic now - that's a whole different thread. I might get around to trying a lighter bullet whenever I get through my pile of 220's

[bob q]

I was typing while listening to my wife say something , so the one group should clearly not be .09 but .90 . Plus the other spelling errors . Yes , single loading for accuracy can be different than what you would use for rapid fire .