338/378 and rl33

[Ronnboe]

I am getting ready to work up some new loads for my 338/378 Weatherby. I am planning on trying 250gr Bergers and would like to try rl33 powder. Any help on a starting load range and any suggestions would be appreciated. Thanks.

 

[can1010]

send an email to berger they will be glad to help out with the info your looking for

 

[Ronnboe]

send an email to berger they will be glad to help out with the info your looking for

Thanks I'll try that.

 

[el matador]

RL33 might be too slow for the 250s. Or maybe not! As far as data goes I'd start around 110 grains and stop when you can't cram any more powder into the case. Max load with the Berger 300s is 118 grains in my gun, which is compressed quite a bit.

I found good accuracy using 107 grains of H1000 behind a 250 grain Accubond in my rifle. Seated to 3.800". This is a few grains below max load but its very consistent, easy on brass, and gives me just under 3k fps.

 

[Ronnboe]

RL33 might be too slow for the 250s. Or maybe not! As far as data goes I'd start around 110 grains and stop when you can't cram any more powder into the case. Max load with the Berger 300s is 118 grains in my gun, which is compressed quite a bit.

I found good accuracy using 107 grains of H1000 behind a 250 grain Accubond in my rifle. Seated to 3.800". This is a few grains below max load but its very consistent, easy on brass, and gives me just under 3k fps.

 

[Ronnboe]

Thanks for the info. The H1000 might be what I end up with. I have been using rl25 which works good but am just wanting to try something different that might be less temperature sensitive.

 

[wboregon]

Thanks for the info. The H1000 might be what I end up with. I have been using rl25 which works good but am just wanting to try something different that might be less temperature sensitive.

From what I've heard RL33 is just as temp sensitive, I did just get 8lbs for my 338 edge, but plan on running that with 300 grainers.

h1000 would probably be a good fit for a 250 grainer, maybe retumbo or the IMR endurans 7977/8133

 

[brentc]

For the big WBY case I would get some Berger 300s to get increased down range energy and wind performance then run it up to pressure with N570 (if you can find some) or RL33. Either will work well.

 

[Ronnboe]

For the big WBY case I would get some Berger 300s to get increased down range energy and wind performance then run it up to pressure with N570 (if you can find some) or RL33. Either will work well.

I haven't tried any 300's I might. My barrel is a 1 in 11 twist so I was thinking it would probably like the lighter bullets better.

 

[Ronnboe]

I called Berger today and was amazed by their customer service. They had never tried rl33 with their lighter bullets but they said they would be happy to work up a load and let me know. About three hours later they called me back with load data. Here's what they came up with for anyone interested. Test barrel was 26", bullet 250gr elite hunter, COAL 3.907, starting load 114.5 gr 2854 fps., Max load 120.7 gr 3024 fps. 98% case fill. I was floored how quickly they helped me.

 

[brentc]

I haven't tried any 300's I might. My barrel is a 1 in 11 twist so I was thinking it would probably like the lighter bullets better.

The stability will depend on your elevation. If you're above 2500 ft above sea level you're golden with your 11 twist. You'll give up a little BC if you go below that.

 

[Ronnboe]

The stability will depend on your elevation. If you're above 2500 ft above sea level you're golden with your 11 twist. You'll give up a little BC if you go below that.

 

[Ronnboe]

I'm up at 4000' and above. I might try some 300s and see how they work.

 

[Iron Worker]

Well what conclusions have you come to ? I just acquired a 338-378 accumark . Its comfortable recoil,but I think I might buy a 5 port baffle brake . Right now I started out with Hornady 230 gr ELD-X bullets and Retumbo . I wonder how RE#26 will work ?