Since I have a bunch of both I thought I would give them a go in my 338 Winchester. Here is what I found today. This was chrono work no groups measured.

Superformance. 225 Sierra Federal case & WLRM primers.
70gr.-2673
71gr.-2710
72gr.-2770
73gr.-2808
74gr.-2858
75gr.-2906
76gr.-2913


Hunter. 225 Sierra same case and primer as above
72gr.-2823
73gr.-2845
74gr.-2869
75gr.-2945
76gr.-2958

The Rifle is a Tikka T-3 Lite SS

All ejected easily and showed no signs of pressure.

Also shot.

IMR 4350 71.5 gr. 225 Hornady IB same cases and primers. 2887 fps and 3 shot group 1 7/8" at 220 yards.

H4350 69.5gr. 225 IB same case & primer. 2861 fps and 2" group at 220 yards.

Sounds like you had a good time.

I did have a good time. Also shot a 300 RUM and a 300 SAUM. This was after the wife and I put a 150 rounds of 380 and 40 cal. through a couple of glocks.

Thanks for the report.
I bought a pound of Superformance and hadn't thought of using it in the 338 WM.
This will get added to the list of powders to try in my new 338.

Shot a couple of groups with both powders and Hornady 225 IBs and 225 Nosler Partitions. Hunter groups were not very good and the Superformance was OK but needs refining. Partitions shot the best at 2.5 inches at 220 yards. I think I am going to try 225 Sierras next.

How many rounds of each charge to get an average?

Super and Hunter were just one shot ladder test. When shooting the groups 4 shots but no chrono used. Groups were shot at 74, 74.5 & 75gr. again no signs of pressure.

That's good velocity for 225's with both powders.

Be interesting to see what kind of accuracy those top loads yield.

MM

Some group shot today at 220 yards.

77.5 gr. R-26 2900 fps 4 shots 2 3/8" 225 Hornady IB

76 gr. Superformance 4 shots 2 7/8" 225 Sierra

75 gr. Hunter 4 shots 2 1/4" 225 Sierra

70 gr. H4350 4 shots 2 1/2" Hornady IB

All bullets seated to fit in the T-3 magazine.

Well that's nothing to write home about......do you have any better accuracy history on this gun? What can it do at 100 yards?

Here's what one of my old 338's would do at 100 yards.........granted it's only a 3 shot group & it takes a minimum of 10 shot groups to be meaningful , but it would do this every time out.

MM

That is some nice shooting..

I am happy with moa groups as long as they are consistent. I have not shot anything over 300 yards with the 338. I have a R-19 load with 225 TSX that does 1.5" at 220 yards. These loads listed are just a bunch of loads I have been playing with for some fun time at the range.

That's more than plenty good............RL-19 with bullets up to 210 & RL-22 with the heavier bullets has always been better in velocity & about the same in accuracy as 4350 in multiple 338's that I've had.

That's a great, great cartridge that can be used for a very wide range of animal.

MM