Has anybody tried Retumbo or RL 25 in the 300 win mag? What velocities did you get? How accurate were they? How did they compare to RL22? I'm mainly interested in 165 and 180 grain bullets. If you've got a good load please list it.

IMO, the powders you are looking at are too slow for the applications you are looking at. I tried Retumbo in my .300 Win Mag last year with 180 and 200 grain accubonds. Got great velocity with the 200's, but couldn't get enough in the case with the 180's to maximize the powder. I assume RL25 would have the same problem. If you are looking at Hodgdon Extreme powders, as I was, look at H1000 or H4831 in either original or shortcut. I settled on H1000 with 200 grain accubonds out of mine. Pushes them right at 3000 fps with no pressure signs. Shoots MOA. If you are an elk hunter for the most part, give the 200 grainer a look. You don't lose much in the way of trajectory, but you do pick up some in the way of weight and energy.

Thanks for the info. I'll try H1000 first in 300 Win. I'm cuurently using RL 22 with good accuracy and velocity, but I wonder about the temperature issue.

I use this rifle mainly to hunt elk, but it doesn't shoot the heavier bullets as well as the 165's. I know this isn't the best setup for penetration but the Interbonds I shoot have held up well the past two years. I got a complete pass through with a 2.5" exit hole on a big bull at 33 yards in the timber last year.

For 165's:
RL-25 From 76.5 grains to 84.5 grains
Winchester WLR Primer

But I found that:
RL-22 From 66.9 grains to 79.5 grains
Winchester WLR Primer
was better.


For 180's:
RL-25 From 64.8 grains to 82.3 grains
Winchester WLR Primer

But I found that:
WMR From 61.3 grains to 75.8 grains
Winchester WLR Primer
was better.


As for Retumbo, I feel that it really isn't useful until bullet weight gets up to 200 or more.