I bought my first 300WM in 1990, a Ruger M77MKII stainless with boat paddle stock. The first thing I did was bead blast every inch of that shiny barrel and action!
Next, I worked up loads with H4350, H4831, RL22. RL22 was by far the best performer back then.
More recently, I have tried H1000, Retumbo and RL25 with 180gr, 200gr, 208gr, 210gr & 215gr pills.
H1000 was very accurate, velocity was down a little, so I tried Retumbo, velocity was good, but accuracy wasn't great. Then I tried RL25, WOW!! Bug hole groups at 300yrds and velocity was also higher than any other powder by a significant amount.
Nowadays, this the FIRST powder I try in a lot of my cartridges, especially those for long range with big cases. Even my 25-06 performs the best with this powder, and my 257AI uses a good dose with heavy bullets.
I would try this if you can get your hands on some.
Cheers.
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