I recently acquired an Interarms Mark X in 458 Win mag. I bought it on a whim and want to do some shooting with it to decide if I want to keep it or my 416 Rigby Ruger Safari Magnum as my big bore rifle.

I've been looking at reloading data and can't find any for RL=15 with 400-500 Grain bullets. I found data for similar burn rate powders but none for RL-15. According to the burn rate chart in my Hodgdon manual RL-15 is slightly faster than Varget for which Hodgdon shows data so I'm thinking RL-15 should work. Alliant doesn't show any RL-15 data on their website.

I have a good supply of RL-15 but no Varget. Does anyone use RL-15 in their 458 Win. or have access to any data they can share?

Thanks,

Woodleigh loading Manual starting loads for .458 Win Mag with 500 grain bullet is 68 grains of RL-15

I reckon it will be too slow for top loads with 400 grain bullets and with 500 grain bullets all the powder you get under the bullet will probaby see 2000 f/s plus.

I foud you can use more Re 15 in a 375 than Varget or 4064.

quote:

Originally posted by Redstone:
Woodleigh loading Manual starting loads for .458 Win Mag with 500 grain bullet is 68 grains of RL-15

Yup,
The rest of the Woodleigh RL-15 data for the .458 WIN-SAAMI is here:

http://forums.accuratereloadin...401085452#1401085452

Please take a gander and leave a comment to support THE MISSION.

Rip ...

Thanks RIP. That's just what I needed. I'm only going to be punching holes in paper for these initial loads to check out my new toy.

WAY WAY too slow of a powder for the 458 straight cases.

rel7, tac, h335 are your friends...

exjecta adds to recoil

quote:

Originally posted by jeffeosso:
WAY WAY too slow of a powder for the 458 straight cases.

rel7, tac, h335 are your friends...

exjecta adds to recoil

Re7 was great. I seem to remember that when used in a 222 as compared to 4198 it was fater burning then when both were used in a 458.