Win 760 for 303 British and possibly 260 rem

My 7-08 loved Win 760 with 140 Sierras so I suspect your 260, based on the same case) would as well.

W760 will work in the 303 and 260. I've used it in the 260 along with other calibers. It is temperature sensitive as most ball powders are.

I don't use it much anymore due to the newer, less temp. sensitive powders being out and for about the same price. That's likely why you don't see 760 being used more. H- 380 is another good example of a decent ball powder, but isn't talked about or used much anymore.

760 is very useable for your two calibers. With things being the way they are now, use it up.

I've always used magnum primers when using ball powders in my hunting ammo. Speer reloading manuals have always recommended magnum primers with the rifle ball powders. If you don't shoot the ammo in very cold temps, you can use regular primers.

Some will argue that cases with case capacity less than 60 grains or so, you don't need a magnum primer. For target loads, I wouldn't worry about it.

British 303 Modern Reloading 2nd edition by Richard Lee~~~~~~~~`180 Grain Jacketed Bullet WIN 760 start 42.9 .........fps 2278 NEVER EXCEED 46.3 fps 2435 46550 PSI minimum OAL 3.075.... I recall big fire balls, in the 30-06... I thought it was a good powder. I did recall having to use Mag primers per book specs. I just don't seem to notice temperature sensitivity, in anything...I like light loads. But shoot what you get...I think you will like it.

Speer is the only manual I have that recommends magnum primers for Spherical powder loads they list. If I understand you correctly you are apprehensive about using mag primers for the 303 British? Or the 260 Rem? Start with start charges and work your way up and watch for pressure signs. Partial FL size to keep case head stretching.

Hodgdon, the distributor of the powder, lists standard large rifle primers with W760/H414 in their load data for both cartridges. I’ve used both powders (identical) in both the OP’s cartridges where they worked well. W760 gave the best accuracy in both my .260s with 120 to 140 grain bullets.





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I use it to push a 100 AMAX in my wife's 260 REM. It's a hunting load so I worked it up in the cold with mag primers.
It definitely gives excellent velocity and accuracy.

I used it in 243 win with 100 and 105 gr bullets as well 7mm08 with 139 - 160 gr bullets. It worked well. Iirc that powder works best with heavier bullet weights.

O/P, you now have the 760. Use it. It will work for both of your cartridges. Unless you are using the rifles in sub freezing temperatures going for the trophy Dall Sheep of a lifetime, I wouldn't worry about the primers, just go shoot.