Looking For 338 RUM Load Data

[JBM_DC]

Been playing around with my 338 RUM for several months now loading up 300 Elite Hunting Hybrids, but am having too much inconsistency at extended ranges. I am about to switch over to the 285 Hornadys and was curious if anyone has some load data for anything 250gr - 300gr?

I will be using H1000 as I have a few 8# jugs of it. A good friend recommended I try RL33 which he says works very well in his 338 Lapua with 300 SMKs.

Right now my go to load for the Bergers is:
Remington 338 RUM Brass
Winchester LRM Primgers
87.6gr H1000
300 Elite Hunting Hybrids at magazine length (.030" jump to lands)
Yielding 2645fps from a 26.5" barrel

Hoping the 285s could put me somewhere around 2725fps with minimal pressure increase, but that seems like a stretch.

 

[Mulligan]

Not exactly what you ask for however it may be helpful.
Remington 700 w/ Stock Remington barrel, defensive edge break.
My 338 RUM liked the 250 gr SMKs. 96.4 grains of Retumbo (2890 FPS in this rifle) was a little sweet spot for this rifle.
It also liked 103 grains of Retumbo behind a 225 AB.

Best load combo I found was 225 Nosler AB, 96 gr of RL-25, 215 primer...down right zippy and sub 1/2 MOA.
CW

 

[RonAKA]

H1000 should work fine with the 285 grain bullets. Hodgdon has loads for 250, 275, and 300 grains. For the 275's they suggest 86 to 91 grains of H1000, with a max velocity of 2729 in a 24".

The Berger 250 grain has very good ballistics for a lighter bullet. Hodgdon data would suggest you could get it up to 3000 fps with H1000, and perhaps a bit more with Retumbo.

 

[GeorgeSpringer]

A buddy of mine shoots a RUM and his H1000 load with 300 gr Bergers is 86 grains with Fed215M's. Probably the first change I would suggest is primers. I have tried several different primers in a 338 Edge and sub MOA groups and single digit ES were with Fed215M primers.

 

[Rust]

I started with a RUM about the time it came out. 300s were not available back then to I ended up with a load of 89 gr RL-25, WMR primer and a 250 gr Scenar at 2950 fps. It proved to be very accurate all the way to 1,000, the longest range I had available.

I haven't bothered with any other load development since. But I will say that over the years there have been lot to lot variations in RL-25. I kept the chrono data from load development so I load a few at lower charge weight to safely see if the current lot is the same.

 

[Whitehunter]

.338 RUM 250 grain Nosler AB RL 25 91.5 grains at 2935 fps ES 8 SD 4
265 grain Barnes LRX- BT H- 1000 92 grains at 2816 fps ES 4 SD 2 This is a 26" barrel on a Remington Action hunting gun. Three shot groups under 1/2" at 100 yards.

 

[Preacher]

Mine seem to like the 250 SMK's and close to 100 grains of RL-33...... with 215 primers..

 

[slm9s]

338RUM Underground Skunkworks, 30" bbl
300gr Nosler Custom Comp
90gr H1000 giving 2760fps

 

[JBM_DC]

Thanks for the info! There isn't much available for this cartridge. Please keep the loads coming!


I just got my scope back from my father and mounted it up last night. I hope to be out testing the 285s over H1000 within the next few days. Still working on my match rifle for now, so this one is still on the tail end of things to do.

 

[Midnightmedic]

300gr Berger OTM seated to aol of 3.980" (0.010" off rifling) with 91.5gr of Retumbo and fed 215m in remington brass with necks turned just to clean up. Factory Remington 700Lh with sporter barrel clocks in at 2850fps. Shooting is all done at 6000'+ feet of elevation. This is a warm load but will hold three shots into 1/2moa out to 1100 yards with bipod and rear bag (best I can hold with 16x tactical scope). My ES dropped to under 10 fps when I removed the decapping spindle on my RCBS full length sizing die so the neck tension is very high with no expander ball. Have about 300 rounds of this load thru the gun and still going. Cold bore first shot consistancy is spot on out to 1100 yards. Never had to fire the second shot on an elk yet, but have not shot one past 750.
I Have tried 99gr of RL33 with same set up and it hits @2900fps with good accuracy, ES is a little higher but under 20fps. Working on how well it does with cold bore shot consistancy.

 

[Midnightmedic]

FYI, I have a Wyatt's extended magazine (cfe-9 on their web site) in my stock which with a little work to action will hold two 4.00" aol loaded rounds. This allows the 300gr Berger OTM to be seated with bearing surface just above the neck/shoulder junction on the 338RUM

 

[Butch1]

I know this post is old. But anyone else have any input? Im currently working up a load for a 338RUM.

 

[effendude]

I have had great success with Retumbo and the 300 gr Berger. I load it to mag length of the AI mags. I believe I am running 89 grains of Retumbo. I went much higher with Re-33 but accuracy dropped off badly. This load shoots well out to a mile in my rifle.Scott

 

[Butch1]

I have had great success with Retumbo and the 300 gr Berger. I load it to mag length of the AI mags. I believe I am running 89 grains of Retumbo. I went much higher with Re-33 but accuracy dropped off badly. This load shoots well out to a mile in my rifle.Scott

Thanks for sharing! What twist barrel? I Have some 300 bergers to try.

 

[Midnightmedic]

Still using the load above; 460 Bergers down the tube and same 100 Remington brass holding up fine. One of those rifles that just doesn't miss. One of the best cold bore shot loads I have seen. Tested in temps from 90+ degrees to -5degrees and elevations from 3400' to 11,200'. Time to get another 250ct box!

 

[Butch1]

Still using the load above; 460 Bergers down the tube and same 100 Remington brass holding up fine. One of those rifles that just doesn't miss. One of the best cold bore shot loads I have seen. Tested in temps from 90+ degrees to -5degrees and elevations from 3400' to 11,200'. Time to get another 250ct box!

How far off the lands are you on the 300 Bergers?

 

[farmer44]

Anyone using Lapua 300 gr. and if so what powder is working for you? thanks

 

[wboggs]

My most accurate load used Norma MRP. Almost 3000fps using barnes 250' s from a 26" krieger. Would shoot a 5/8" three shot grp at 200 on a good day.

 

[Rdlningcltchdmpr]

If you're just hunting out to 500 yards, the 160ttsx barnes with max load R17 or us869. R17 being highest velocity. My 338 lapua gets 3900 fps 3/4" groups or less. Very low recoil and does not over damage deer.