In a pair of Model 70 458s I use to own 70 grains of 2206 did just under 2050 f/s with both the 500 grain Hornady and 500 Grain Woodleigh. They had 22 inch barrels.

I can't remember the exact load but 2207 was also very good. I think the laod was in the 67 grain area. The 2207 did around 2130 in a 24 inch barrel Ruger Number 1.

Mike

I;ve hunted Water Buff in the NT a few years ago and have the following observations. You will be doing a heck of a lot of walking and very little actual shooting. Make your .458 as light as possible. You will shoot a 50 yrds or less so a scope is optional. I used a .458 I built on a M98 mauser with a 24 inch barrel in a Bulter creek stock. I used a leupold 2.5X compact scope. the load I used was 59 grs of RL-7 and a 500 gr Woodleigh. It took three days to find a good bull and one shot through the shoulder. He went 10 ft and piled up. I must have walked 30 miles in those three days. Made the mistake of hunting with a 20 year old guide.I was very glad i had a light rifle.-Rob