Best 338 Win Mag powders?

[Ray123]

Depends on what you want, high velocity and energy, don't always go with great accuracy...
338 WIN MAG is for hunting, at moderate ranges that I shoot ...so I run heavy bullets at highest speed, like 275 gr bullets at 2675 fps with RL-26.

 

[65swede]

I shoot 225gr accubonds and R23 in a Model 70 that has a weatherby length mag box and bolt stop. .040 jump nosler brass wlrm.

.75-1.0 moa, start at 71grains.
Mine tops 2900fps

Not my most accurate hunting rifle, but it crushes Elk.

 

[FNSafari]

Your rifle and bullet combo, seating depth will tell you. IMR 4350, H4831, RL 19, 22 just get a good loading manual and start the process of experimenting to see if there is a marked preference for one powder vs. the others.

 

[20VarTarg]

I love my 338 Win Mag but I rarely shoot it because the recoil just isn't pleasant. I run RL 19 and H4350. I have 2 loads using 2 different bullets. Best 3 shot group I ever shot at 300 yds was with the 338 Win Mag. Maybe the kid the rifle was built for just isn't ready for the BIG BOOMER. Some shooters will get a flinch with the recoil.

 

[FNSafari]

Nice thing about a caliber like the 338 win mag is it can be loaded down.

 

[fgcook]

Working up 338 WM loads for a moose and grizzly hunt. I have quite a few powders, hopefully going with a 210gr bullet. I have 16# of H4350 and some others that have been used. Any recommendations and weights to look at?

 

[L.Sherm]

Working up 338 WM loads for a moose and grizzly hunt. I have quite a few powders, hopefully going with a 210gr bullet. I have 16# of H4350 and some others that have been used. Any recommendations and weights to look at?

Nosler reloading manual or Google is your friend.

 

[Coyotefurharvester]

When I was working on an elk load for my 338wm, I settled on H380 because that powder changed the way the recoil felt. It allowed me to test/practice in the summer tee shirts. I used 200 gr accubonds, only issue, no exit always found the bullets under the hide.

 

[PhilC]

Working up 338 WM loads for a moose and grizzly hunt. I have quite a few powders, hopefully going with a 210gr bullet. I have 16# of H4350 and some others that have been used. Any recommendations and weights to look at?

Nosler's data is free online - https://www.nosler.com/338-winchester-magnum

 

[ebb]

If the owner is going to target shoot maybe the low burn temp of Hybrid 100v would keep the throat alive longer?

 

[akph24]

Hello

I have been using a 338 WMG as guide in alaska for 12 years....

the best powders were Norma MRP and VV N560. with A Nosler 250 gr. PT + Norma Brass + CCI 250 got 2750fps.

 

[Alaska Bush Man]

Did you use a saami spec reamer? What's your freebore?

No reamer ! I seat at Standard COAL for bullet !
For me Reloading manuals from Early 80’s from Nosler 1 manual to present has lost all credibility.
None of my load’s chronograph compare to manuals too low on velocity.

 

[Alaska Bush Man]

We’re just starting to shoot a new build in 338 Win Mag. I’m using 225-230 grain bullets. First loads were with IMR 4350. I’m looking for anyone that has experience with this cartridge to suggest good alternative powders. Best group from the first 50 shots was 3/4”, using 61.4 grains and a 230 set at touch.

I have great results with RL19 and IMR 4350 with 225gr Nosler Part.
At 61.4 of IMR 4350 with 230gr you are very underloaded in 338 WM.

 

[centerlineseal]

IMR 4350 with 225gr Nosler

Same here, but with Accubonds. 3 shot group from an old Pre-64 Win Model 70 was sub 0.5 MOA.