Re: 338 Norma Review By Ward W. Brien
In my opinion, the Ramshot was a little too hot for the altitude. Up here, (8200' ASL) 1/10th of a grain makes a noticeable difference. Powder has its own O2, however at my altitude the O2 is decreased by (I think) 30%. So, when the bullet makes its initial jump and the combustion/flame is exposed to the atmosphere, the burn rate is different.
When I first moved here from Los Angeles, the loads for my .300 Win Mag didn't work. I went from shooting very small groups to 1+ inches at 100 yards. After many attempts of rectifying the problem, an acquaintance of mine told me that I needed to go to a slightly slower burning powder and that 1/10th of a grain made a difference. So, I changed from IMR 4831 to H4831SC and it worked.
I have heard from others that the Ramshot Magnum powder and the Winchester Large Rifle Magnum primers work very well at lower altitudes. So, there you have it. I'm now back at working up a load for a new .338 Norma that Mark Chanlynn built for me, and I am again utilizing the RL22.