The 6.5-300 Weatherby has lots of advocates here in Wyoming, based on the super-flat trajectory. That said, you need to be shooting the bullets with the highest ballistic coefficient to help manage the wind here in Wyoming. Where you are, you probably have much less wind.

Here's a nice article from Handloader magazine from a few years back on the 6.5-300, and reloading for same:

https://weatherby.com/wp-content/uploads/2022/07/65300_Loads.pdf

The downside of the 6.5-300 is that it is a barrel burner. It is a highly "overbore" cartridge, meaning that it is trying to shove a tremendous volume of burning powder down a small cross-section hole in the barrel.

The amount of powder in the 6.5-300 case (75+ grains) absolutely needs a 26" barrel to burn it all up. If you go with a shorter barrel (24 or 22 inch), you're going to run into a situation where you're trying to use a faster-burning powder... but because there's so doggone much powder you have to burn, you'll start seeing pressure signs. Which means you'll have a non-optimum load, settling for lower pressures (and lower muzzle velocities) than you could achieve with a longer barrel and slower powders.

Here's a table of cartridges laid out in a table and spectrum of "less to more overbore:"

https://bulletin.accurateshooter.com/2014/03/overbore-cartridges-a-working-definition/

See the numbers in the right-hand column? The thought among gunsmiths is that when the computation of (case capacity, in grains / cross-section area of bore, in inches) is greater than 1,000, you start seeing rapid barrel wear just forward of the cartridge (ie, the throat).

The 6.5-284 cartridge and the .243 Winchester start to see their groups open up their groups, according to people shooting them for group size, at or around 1,200 rounds total. For comparison, the 6.5-300 Weatherby has an "overbore score" of 1,753. That's using 96 grains of case capacity from the first URL I listed above.

One thing I know I'm going to hear from people is: "What do you mean, these barrels only last 1,200 rounds?! Look at the .50 BMG! Those barrels last thousands of rounds on a machine gun!"

Yes, those barrel do last a long time. Here's why:

https://i.ytimg.com/vi/0SnHc0avZRA/maxresdefault.jpg

Please look at the cross-sectioned barrel picture closely. Do you see that liner in the barrel for the first, oh, 7" or so in front of the cartridge? Look closely on the top side of the section, and you see the boundary between the liner and the outer part of the barrel? The liner which is the bore for the bullet is made from "Stellite," an alloy of steel that is absurdly hard, and very temperature resistant. That's how machine gun barrels last so long, even with an overbore cartridge like the .50 BMG. The barrel in the picture is for a M60 machine gun, which is a .308/7.62x51 NATO, which you see in the chart of overbore cartridges is pretty easy on barrels. You also see that the .223/5.56 round is easy on barrels, and you'll notice that the cartridges that lots of accuracy/match shooters are using are pretty easy on barrels (6.5x47, 6mm PPC, 6 BR, etc). M2 (ie, .50 BMG) machine gun barrels also have Stellite liners in them for several inches in front of the chamber. That's how they last so long. 

But the numbers on the 6.5-300 for trajectory are outstanding. It's one of the flattest shooting cartridges that shoots a bullet heavy enough for large game. I probably wouldn't use it on Bison, bears, or moose, but pronghorn to elk, I'll bet it works dandy.

Anyway, you now have an idea of how hard on barrels the 6.5-300 could be. But if you're just going to sight it in, and then use it for hunting big game, and you're not target shooting or hunting varmints with it, you might never go through 800 rounds while you own it and are hunting with it - and so it might work just fine for you. There's a great selection today of 6.5mm bullets, and it is getting better all the time.