I've been shooting a .270 WBY for a few years using RL 22 for the most part, and I'm working on RL 25 loads. Has anyone here worked up loads with the newer slow powders? RL 25, Retumbo and Big Boy should be just the ticket for the .270 WBY, with lower pressures to boot, but there doesn't seem to be any data out there to start from. I'd be interested in the real slow surplus powders as well, WC860 and WC872 BD

I've used RL25 in my 7mm Rem Mag with 130 gr. Barnes XBT bullets. I got 3420 fps avg. out of my 26" barrel.

This powder may work even better in your 270 WBY.

I think the new slow powders will be great in the .270 WBY. The problem is that there's just no data out there to start from. BD

73.0 grains of H1000 pushing a 140 grain Barnes X is the best load I have found for a buddies .270 WBY that I load for,it is a Weatherby Ultra Lightweight.

My friend has a .270 wby custom job by rifles inc.
It absolutely loves 74.5 re25 under a 150 grain hornady spire point. He never gave me a chance to chrono it but there are no signs of pressure and it shoots cloverleafs if he does his job. He has a huge pond in front of his house and he has a custom reticle by premier reticles that is calibrated to 600 yds. Anything that approaches his pond by land or air that could eat his fish stays where it lands!!

Here is a load from Hodgdon.com (26" barrel)

130 gr. Speer SP/H1000 81.0 grs. 3259 fps

150 gr. Nosler Part./H1000 79.0 grs. 3132 fps

Also, there is data for the 270 WSM, which is pretty close in capacity to the 270 WBY.

http://www.hodgdon.com/data/rifle/270winshortmag.php

[ 01-03-2003, 13:26: Message edited by: todbartell ]

Thanks for the replies.
Kraky, I've had good luck with 75 grains of RL25 under a moly'd 150 grain partition for 3,180 fps out of my 24 inch tube. However I have no idea what sort of pressure I'm developing so I'm not going any farther, and I'm tempted to back down a grain.
Todd, While the Hogdon data for the .270 WSM is useful as a demonstation of the relationship between Retumbo and H1000, the WSM and WBY cartridges are significantly different. Looking at Hogdon's data for 150 grainers, in the WSM the H1000 max charge weight is 67.5 grains and that's listed as a compressed charge. For the WBY the max charge weight is 79 grains of H1000, and that is not listed as compressed. I suppose I could chrony the max charge of H1000 and then work up to that same velocity with Retumbo. I'm really more after consistent accuracy at a lower pressure than more fps. BD

Not a new powder but you might consider IMR7828 powder, it works great in a 270Wby.. 3500fps with a 130gr bullet.

Good Luck!

I also use IMR-7828 for over 3500 FPS from my friend's .270 Weatherby - and it shoots great with no pressure signs.