I’m looking for load data using Reloader 15 in the 416 Rigby. Can anyone shed some light on this please ?

Might be a bit too fast for decent performance.

You can use any powder, for any caliber, but you will not get optimum performance with all of them.

I agree with Saeed, I tried RL 15 in my CZ and couldn’t get a load with the velocity I was wanting before pressure signs became evident. For hunting loads I use RL 22, good velocity and good accuracy.

H4350 is my preferred powder for the 416 Rigby.

I’ve seen load data for RL 22 (and RL 19). I’m thinking the 19 would be better for 350 grain bullets

I agree that Reloder 15 is too fast, you will hit pressure maximums before you get a reasonable velocity. If this is a case where you have a boatload of Reloder 15 and are looking to use it during the powder shortage IMO you would be better to wait things out. If you are lucky enough to find some IMR 7977, which is one of the new Enduron powders, you will do well to try that. I am getting close to 2600 fps in my 24" Ruger barrel and very good accuracy. The Enduron powders are very temperature stable and I have found them to be easy to work with gentle pressure/velocity curves.

Good luck,

Paul