Would like to tap into the knowledge base here, if I could. I have acquired a 338 Ultramag. Was wondering if anyone on this forum has some loading experience to share. I will use the 250 Partition. Thanks in advance, Eagleye.

If you don't find what you're looking for here, the guys at http://www.24hourcampfire.com also have quite a bit of experience with that round. Good luck.

AA-2700 From 64.8 grains to 72.0 grains
Remington 9-1/2 Primer
AA-3100 From 78.8 grains to 91.0 grains
Remington 9-1/2 Primer
AA-4350 From 74.3 grains to 82.5 grains
Remington 9-1/2 Primer
AA-5744 From 38.0 grains to 42.0 grains
Remington 9-1/2 Primer
AA-8700 From 93.6 grains to 112.9 grains
Remington 9-1/2 Primer
H-1000 From 86.5 grains to 99.0 grains
Remington 9-1/2 Primer
H-4350 From 67.9 grains to 83.0 grains
Remington 9-1/2 Primer
H-4831 From 77.2 grains to 90.0 grains
Remington 9-1/2 Primer
IMR-4350 From 69.8 grains to 79.0 grains
Remington 9-1/2 Primer
IMR-4831 From 72.1 grains to 89.0 grains
Remington 9-1/2 Primer
IMR-7828 From 80.4 grains to 92.0 grains
Remington 9-1/2 Primer
Magnum From 87.9 grains to 97.5 grains
Remington 9-1/2 Primer
MagPro From 85.8 grains to 96.9 grains
Remington 9-1/2 Primer
MRP From 82.0 grains to 87.0 grains
Remington 9-1/2 Primer

N-560 From 80.5 grains to 92.1 grains
Remington 9-1/2 Primer

Retumbo From 84.4 grains to 101.0 grains
Remington 9-1/2 Primer
RL-19 From 76.7 grains to 82.5 grains
Remington 9-1/2 Primer
RL-22 From 80.0 grains to 89.8 grains
Remington 9-1/2 Primer
RL-25 From 82.8 grains to 95.0 grains
Remington 9-1/2 Primer
WXR From 81.4 grains to 91.0 grains
Remington 9-1/2 Primer

I like the N-560 loading...

Hello Eagleye,
Congrats on the 338 RUM, I think the 338 & the 375 are the best on the ultra mag line.
I have used alot of diff. powder and bullets. What works the best in my gun is VihtaVuori Powder N 560. I use 93.5 gr. 250gr. Hornady Sptz. Interlock. Fed.215. This load will do 3040 fps in my gun. The group size is about 1/2-3/4 inch at 100 yards. This is a max. load in my gun. So work up to it if you wish to try it.
A buddy of mine uses the same powder and bullet, but he has to use 1gr. less powder.
I have taken one Elk and one big Alaska Black Bear, With this load. Bear shot at about 50 yards, Elk 468 yards both Animals died on the spot with the bullet making a complete pass.
Good luck..
hammerdown

Congratz on getting into a big 33-I've used one for quite a time-I use the 340. The two are the same for all practical purposes-I've used the 250 Noz quite a bit. It'll become a fast friend of yours.

"GET TO THE HILL"

Dog

Cool, the .338 is a long time favorite of mine. 250 grain bullets have a sectional density of .313, and the case has the capacity to launch those bullets at 3000+fps.

I just cooked up some 250's with IMR7827 last month. Impressive load, didn't seem to kick as much as my old .338 Winchester.

packrat

Fine rifle,most of the guys have good accuracy with this caliber.My pet load Hornandy 200 grs Interlock(3310),federal 215,case Remington,H-4831sc 95 grs(not max.)3.585"),trim 2.751",full lengh sizing RCBS,seater LEE.Play with AOL.I can get near.500MOA

I too, like the N560 for the 250 grainers. In my .338 RUM the absulut max is 94 grains.
But I've also tried some Norma MRP, and here is my max, 90grs. on those bullets.
I dont like the muzzleflash with the n560 though.