Ok, guys if your going to do these comparisons then do them at the same pressures. The .375 H&H will give you over 2600 fps. at 60 K psi. that being the quote from both the A Square book and the Lee book. Does anyone have any pressure data, theirs or manuals, for the 9.62 ?
But ALSO same barrel length! I had a 22" .375 H&H and no matter what I put into it, or how much, it wouldn't get anywhere near 2600. About 2530 to 2550 fps was absolute max, and I'm sure that was at much more than 60,000.
My Tikka has a 22.4" tube. I'll not vouch for pressure as I have no way of measuring it other than a computer program. There's no data that I could find for RL-17 in a 9.3 X 62 other than RealGuns, and their data gave the best results of ANY powder overall for accuracy and velocity, from a Ruger African (23" barrel).
It was that info that got me trying RL-17. At first I was not happy with it as I was not getting near the results suggested by that source. After all the burning rate is supposed to be equivalent to IMR4350, which I knew would be too slow. However a friend encouraged me to give it another try using more of it. Since I can seat the N.P. to magazine length, I can crowd in another 4 or 5 grains. All I'll say is if you want the data go to my website and read the disclaimer as well as the data.
It APPEARS to be safe in MY rifle. But more testing is required. Another poster mentions 2550 from the 286 NP in a 24". From my initial trial, I'd say that's easily possible using RL-17... IN MY GUN!!! He didn't mention what powder he was using.
All I'm saying, and I've done the profiles using 2 different ballistics software, is that the 9.3 X 62 is in the same ballpark as the 375 H&H, when each is loaded with the best NP available for each, barrel lengths equal.
I did get 2700 fps from a 26" .375 H&H using a 300 NP, but the rifle was so inaccurate I gave up on it for a 340 WBY. The M70 I had in .375 H&H (24") wouldn't make 2600 fps from several 300s no matter what I did to obtain that MV. As we all know, rifles are individuals... that's why I emphasize "IN MY RIFLE"
Bob
www.bigbores.ca 
