There is no free lunch in physics.
The 264 Win Mag is a very fast cartridge. It burns a lot of powder and pushes a lot of gas through a pretty small hole. It has a pretty short life span on its barrel too.
The 26 Nosler is based on a 404 Jeffery shell (case body, with a slightly smaller rim diameter as I understand it. At least that’s what I am told) so it should burn a bit more powder and burn out the throat a bit faster.
I have built several 264s in my life and I have loaded a bit of ammo for them. I have done the testing both for accuracy (which could be excellent with good barrels) and for velocity, which I found to be not as impressive as I’d hoped. I have never gotten 3100 FPS from a 264 Win Mag with a 26” barrel with a 140 grain bullet. I come very close, but I can’t reach it safely.
I have also built a few 6.5-06 rifles and done the same tests with them. They have been about 65 to 75 FPS slower than the 264 as a rule, but just as accurate.
So without looking at the slick advertisement and looking only at the laws of physics, we should be able to come up with a realistic expectation of the performance of the new 26 Nosler. It’s probably going to beat the old 264 Win Mag in velocity by a small margin and its probably going to burn about 6 to 8 grains more powder. If the barrel lengths are equal I doubt it’s going to give us all that much more than the 264 does, but it is going to cost even more barrel life.
The first problem we have with short barrel life is load work-up. To get a rifle ready to shoot long range (say over 600 yards) we need to have the load down pat. We need a very high degree of accuracy and we need to learn the trajectory and wind drifts as well as the holds for shooting at up-hill and down hill angles. Doing all this takes a bit of time and some shooting.
In the learning, we often burn out a barrel or at least come very close to the end of its life for such precision shooting. So we need to look at such rifles with at least 2 barrels. When you refine the load for one barrel however, there is no guarantee that barrel #2 is going to like the same load. If it does, you are good to go, and all the knowledge and experience you gained burning up the 1st barrel will now serve you well in the use of the 2nd barrel. If however you are not so lucky, you need to start all over again. Many rifle barrels do not always shoot their best when you run them at maximum pressure and velocity. So if one barrel requires a slower of faster velocity (or even a different bullet and/or bullet weight) all your research with barrel #1 is of no great value.
This is why I am not enthralled with velocity in and of itself. As a gunsmith I can build what ever I like and the cost to be is identical regardless of what I build. I am not one who will defend what I have just because I have it. I can change it easily at any time if I find something I like better.
So far I have not been impressed enough to change to a “super mag’ in any caliber.
I believe most of it is just advertizing for the purpose of selling products.
I hope to be proven wrong sometime. Better would be better. I am still waiting to see the overall results. Faster by itself is not usually better. Faster means you need a stronger (and more expensive) bullet. Special brass is also expensive. More powder cost more to fire per shot. When it’s all finished, I ask the question;
What’s the mission of this rifle?
If the mission statement is to kill 10-20 animals in the next 20 years I look at the package in a different way than a rifle I shoot a lot and kill everything from prairie dogs to moose with and shoot every month of the year.
I shoot a lot. I don’t like barrel burners for that reason. I also have not seen any advantage in the actual killing of game with bullets that leave at 2900FPS and bullets that leave at 3300 FPS. Faster can do well, but instant death is still instant.
