For the 26-Nosler, barrel life needs to be taken into the equation.
I am very fond of the 26-Nosler case design. Just not in 264 caliber. I have reamers and rifles built for it necked up in 277/26-Nosler now being called 27-Nosler, 284/26-Nosler now 28-Nosler, 308/26-Nosler aka 30-Nosler and 338/26-Nosler.
The powder to bore ratio, over bore ratio is higher than a 7mm RUM. So my recommendations are:
#1 When sighting in, testing loads, or rechecking, wait, wait, wait between shots. 2 minutes or more.
#2 Assume you will change the barrel after 600 rounds. If it lasts longer great, if less, well .....
#3 Put a dollar in a jar for each shot taken. LOL.
The .264 WM is, like all the belted magnums a known. No where near as over bore but if you push it to maximums and shoot fast barrel life can still be an issue. Not pushed and shot slow, a barrel could last a lifetime. Note: Anyone who says they can get the same external ballistics from a belted magnum in .264 is going to have to push the powder charge into the same over bore realm as a 26-Nosler so barrel life, barrel life, barrel life.
You makes you choice and you pays you money.