I just bought a new custom 300 Win Mag, and this is my first 300 win mag. I have loaded extensivly for the 300 wsm, but I have some questons,

- What are the best temperature insensitive powders for the 300 Win Mag?

- Is RL22 the most common powder for the 300 WM?

- I have used H4350 in the 300 WSM, is this also a good choice for the 300 WM?

I will be using 180 Accubond, or TSX, and the rifle has a 23" barrel. Any recommended loads are appreciated.

Thanks

RL22 is an excellent propellant for the .300 Win Mag - I have used it from 165 - 200 grs bullets with good results.

The H4350 can also be used. Personally, I would probably use a powder of this burn rate for 150 grs bullets, but it will surely work, also for heavier projectiles.

I have never loaded H-(or IMR-)4831 in a .300 Win Mag myself, but from the burn rate here, these powders would be perhaps a tad better suited than the 4350s.

180 grs AB and TSx are great choices. I personally like the 168 grs TSX: a tad extra velocity, and still offers great penetration.

Of all the magnum calibers, the .300 Win Mag is one of the more balanced offerings.

- mike

I have shot the .300 Winny since 1973, it has been responsible for some of my best trophys, my son now claims it. I shot all powders and primers and by far, my rifle likes 76-78 grains of RL-22 and a Fed 210M primer behind a 180 grain North Fork or Nosler Partition bullet. 8 friends in my Elk hunting group shoot the same load with great success each year. Good shooting.

IMR 7828, RL-22, and RL-25 are all appropriate for the .300 Winchester. IMR-4350 is on the fast side for all except the lighter bullets -- and why would you be using lighter bullets in this caliber?

I have been useing R/L 15 for 150 SP loads with great results. I use R/L 22 for heavier loads and havn't found anything better out of my 300 Win Mag. Mine is a SAKO 75 finnlight. I've also heard of good results with IMR 4831 but i havn't tried it yet.

4831 has worked the best for me and my 300 chums.

Another vote for H4831

I guess I'm odd man out. I used IMR4350 and 200gr bullets. My velocity was @ 2850+ and accuracy was very good. I tried several powders, among which was 4831, but 4350 gave me the best accuracy.

I have had good luck with H4831 and 180 grainers and 7828SSC with 150 grain bullets

RL 22 is my choice with 180gr Accubonds in my 300WM and same for a couple buddies.

7828, H1000, Retumbo and WS780 might be some other powders to try. I believe the WS 780 is whats used in the WS factory ammo for 300WM and other calibers.

Winchester 780 Supreme....try it for 165 grners.
My 7 Mag loves it.

http://data.hodgdon.com/cartridge_load.asp