YIKES!

I do not, will not, attempt that - beyond me & my short 47 years in handloading.

I also find it interesting, that duplex/triplex loading was only attempted once that I am aware of, with the .454 Casull Handgun, and that this practice disappeared within a couple or three years of it's inception/declaration. Why? Is it too dangerous for sporting arms? The .454 Casull handgun was a 60,000PSI gun, yet did people still had trouble with it and the duplex loadings?

I have never heard of this type of loading being successful in rifle ctgs. I suspect if it were, manufacturers would be using it, especially the American ctgs., to have Faster and Faster ctgs. I suspect type of loading is fraught with danger.

Instead, new powders are developed to produce higher speeds and ballistics- like the VV line and some that Hodgdon is marketing, like Leverrevolution, CFE 223, 4007C, 8208XBR and the even newer and slower powders released this year.

I do, however suggest that a suitable action is acquired that will allow full length magnum loading - perhaps a P-14 or Model 1917 Mauser, or a Brevex Mauser action.