The Nosler 260 should make a good leopard bullet with almost any loading.
And I have heard reliable reports of brass failures with DT rifle ammo ?

Phil Shoemaker
Alaska Master Guide,
Alaska Hunter Ed Instructor
FAA Master pilot
www.grizzlyskinsofalaska.com

Anyone who claims the 30-06 is not effective has either not used one, or else is unwittingly commenting on their marksmanship.