I've got best accuracy with medium burners, 4895, 4064 and other powders in that range.  4350 does well too.  I've played with a lot of different slow burners, but when I get up over 40grs with them, the accuracy isn't there anymore.  I'm loading 168 and 190BTHPs, so there's a jump to the rifling.  My Garand doesn't care about that jump, why should my Krag?  Actually, if you keep rounds below magazine length, even the 220RN has considerable jump.

I load the 220 grain Hornadys with 42.5 grains of IMR 4350.

Amen to that!  41 grains of 4350 is about as hot as you want to go in a Krag, and even that is pushing it.  40.0 is the normal loading, and you should try to stick right around there!

I tried the 42.5 grain load and cracked the lug on my 1896 bolt somewhere during two 5-shot strings.  That is the level of velocity & pressure that caused the highest velocity military ammunition to be withdrawn from service.

Anymore, we use what we can get.

reincarnated wrote on Jul 5^th, 2015 at 12:10am:


Maybe, maybe not.  I think the fit of the locking lug into the recess has a bit to do with cracking bolts too.  Some only bear on one edge, like one I took out of a 13000 serial rifle that had a cracked receiver.  On the other hand, I've shot some loads out of my parkerized 92/96 that had to be near proof levels.  The lug fully bears on it, as does the guide rib.  Was it you who said your chamber was out of alignment?  Maybe it was someone on another forum.  That could have some effect on whether or not a lug cracks too.

On to other things, I have decided on my Camp Perry load.  29.5gr of SPP210, a Swiss made powder that burns about 4198 speed.  The 168gr Nosler match bullet is only going around 2250fps.  I shot a lot of loads before deciding on this one.   None of the loads with 40gr or more powder come close to this one accuracy-wise.  I think that has something to do with muzzle pressure.  I shot five yesterday, 3Xs within an inch, one 10, one 9 that I'll take the blame for.  About a 1.75" group with the just outside the 10 ring 9.  I was using a 6 oclock hold at 100yds, 3.3" high at 100 should be right on with a center hold at 200.  Which is right where the 1902 sight is set!  I'm ready as I'm going to get.

Muzzle pressure, the pressure the gases behind the bullet have at bullet exit.  With faster burning powders in lower doses the powder has generated all the gas it's going to long before the bullet gets to the muzzle.  So what gas has been generated is constantly expanding with pressure getting lower behind the bullet.  The more powder you use, the more gas you evolve, more = higher pressure at bullet exit with slower powders, if equal chamber pressure loads are used.  More gas = more blast at the muzzle.  This is my simple explanation, maybe parashooter could illustrate a few loads for us.

The SPP210 was a surplus powder once offered by Wideners.  SPP = Swiss Precision Powder.  After digging around I think it was a lot of Vectan Tu2000.  Some Vectan powders are being imported, can't say if it includes Tu2000.  Ask your local supplier, he'll probably get a smile on his face like the owner of the junkyard did when I asked about an ECU unit for my 89 Volvo.  No words needed said.

By the way, my load was super at 100yds, easily holding the 10 ring with 3/5 in the X, but it was not good at 200.  I think because of transitioning below Mach 2.  Shot dispersal was pretty wide.