Home Forums Hunting & Shooting Ask The Gunwriters IMR 4320

I am usually concerned with accuracy over velocity so... Last fall, when I was finishing up the 30-303 Book (a 303 British, but using a .308 barrel) I noticed that almost all the accurate groups were shot with newer powders. I tried the old standbys too, but most could not match the latest burns.

IMR 4320, a good powder for 308s, 303s and several other mid sized cartridges, managed to hang on with a couple of loads. 4320 and some other old timers, were eclipsed by Varget, IMR4451, Re 15 and Re 17. While Varget and Re 15 aren't brand new, they are much younger than IMR 4320, 3031, 4350, etc.

If you have a cartridge that likes 4320, you either have to buy up 4320, if you can find it, or start experimenting with the newcomers.