Having a number of rifles in various calibers I would build a 300 WinMag because it's capable of meeting short range and long range requirements and the recoil is manageable. The range of bullets and their effect on small to large game are proven. For MY purposes it's bullet weights and Ballistic Coefficients cover many aspects for target practice and the hunting of big game in the USA. With excellent barrel life. When throat erosion effects accuracy you can cut the barrel back and re-chamber it and your good to go.
I've been a 300WM shooter for over 40 years. It's been an outstanding "Go to" rifle when hunting in high and low altitude in desert and mountain terrain, across canyons and ridges and difficult wind condition, high heat and -25 degrees with winds blowing over 20+ mph.
I'm impressed by the 338 Edge, 338 Lapua and the 338 RUM. The 300WM can perform 80% of the shots I've made with authority and limited meat damage. The 338's are superior when you start shooting 1000 meters+. Having both the foot pounds of energy, feet per second, and wind stability. But, elk I've seen killed by a few 338's were DRT with allot of meat destroyed. To gain benefits with the 338s requires longer barrels and muzzlebreaks. Plenty of trigger time, and significantly more powder and large quantities of brass. This equates to more $$$$$ spent loading ammo in a year of shooting.
At 65, I believe if you want it, buy it. If you can't afford it, sell anything your not using to pay for your new toy.
Gonzo
SEMPER FIDELIS