Does anyone know which powder the weatherby factory 340 ammo with 250gr SP is using? I know it is 86gr of some extruded tubular kernal powder similar to IMR4831. I think it might be MRP or maybe RL22. I would like to replicate this load. It is 100fps + faster than the loads I have been building with RL19 or IMR4350.

I believe Norma manufactures the Weatherby factory ammo, so the powder is probably MRP or MRP 2. I find with my 340 that 83 gr of RL22 gives me 2990 fps (chrono'ed) with a 250 gr bullet. - Dan

Thanks Dan. Wow, 2990 is smokin! I think RL22 makes sense for this casing size and bullet weight. I shoot Sierra 250gr boat tails and so they are a little long for powder charges much beyond 85 grains. I got some load data from the guys at Sierra the other day for this bullet. One load was a max load of 80.8 gr RL19 and the other was a max load of 90gr of RL25. I don't think I can stuff 90 grains in there and get the seating depth I need. So the RL22 is probably a better choice. By the way, this data from Sierra was worked up in a new Savage chambered for 340WB.
I tried the 80.8 gr of RL19 and it was very accurate with velocites around 2750 in my MkV. Just not as fast as I would like. Thanks again.

If you want max velocities from the Weatherby calibers, try IMR 7828. You can find max loads for it in the IMR loading guide, which gives a separate chart for the Weatherby calibers, using 7828 powder.

Edard, my 340 has a 27" gain twist barrel, and I believe that some of the speed comes from that fact, both the length and the twist I mean. Still, it's a great hammer, a little muzzle heavy, but it does the job. - Dan

Thanks for the responses. Lloyd, I'll look at the IMR data. I've got to get on the stick this week. Next Saturday I go elk hunting.

My all time best Elk load for my .340's is 90 grains of RL-19, Fed 215M primer and a Barnes XLC coated bullet. For me it averages approximately 3075 fps and is extremely accurate. I have killed several Bulls with this load and have not failed to get an exit hole yet, no matter where I hit the animal. It will drill both shoulders with no problem. I usually find a petal or two on the edge of the off side hole. I shoot a Weatherby and Sako and both handle it well. I would not start that high, you know the reloading maximum of climbing the ladder, etc.

I spoke with a Weatherby Ballistician about eight years ago regarding the same question. At that time, and I'm sure it is still true, he told me that Norma used MRP to load the .300 and .340.

Reloader 22 and Norma MRP are classified as a "same as" powders as they are made by Bofors in Sweden to the smae specs. Although I have gathered that Rl-22 has a slightly different deterent coating.

I have had excellent luck with Rl-22 and IMR 7828 in my 340. I average around 2,950 fps with a 250 gr Nosler Partition in my .340 using 86 grains on RL-22 in a WBY case and a Winchester Large Rifle Magnum primer. This is out of a 26" barrel.

[ 10-14-2002, 23:44: Message edited by: DavidReed ]

Thanks everyone. It's great to be able to draw from your experience. I think I'm convinced at this point to go do some more test loads. I appreciate all your help.

I don't know which powder Norma use for their wetherby loadings but my guess is that its 1230 which is a bulk powder simular to MRP.

I my self use 90 grains MRP with fed 215 primer and 250grains bullets used Nosler Partition and Lapua Mira so far.

Sorry I don't have a chrono, but its Normas own recommended load.

Regards

Mads

Edard -- I just started working with the North Fork 240 grain bullet with my .340, and it looks very promising. I have used the 225 grain with good results in the past, as well as the 250 gr. This 240 grain is proving to be a very accurate bullet in both my rifles. It should be a real nice larger game bullet. Mike Brady said in his note that came with the bullets,that it should be a real bone crusher for Africa. Good shooting.

Hi.
Check on Norma's site:
www.norma.cc