I recently bought four boxes of these. I'm using them in my 30/338 Win Mag. I am in Love. 65.2g IMR 4350 runs 2,800. Shoots into a 1" five shot group at 200. My gun has a 26" Schillen tube on it. COAL is 3.420" which lands right on the rifling and is a single feed only deal. I would LIKE to use a finer powder as weighing each charge rather sucks as we all know. Thrown charges tend to vary .1 to .2g. I have several # of Alliant R-17, which is a little slower and alot finer than the IMR 4350. Anyone have any ideas as to a Safe place to start. Fwiw I contacted Alliant and they said they don't have a barrel in that caliber and good luck and thank you for choosing their products. As a last resort I could just suck it up and buy the chargemaster I've been eyeing for a while now. TIA