I would suggest a .338 LM. My current favorite.
A bit heavy, it owns a bi-pod.
I was taught to shoot from an object, sitting or prone. Thank you, dad for teaching me, back in the early to mid-1960s decade.
I use Norma brass, 330 grain Bergers, a 50 mm collecting lense Vortex, the model escapes me. The name of the powder ran out of the space between my ears.
I was using factory ammo, and was lucky to hit paper at a 1/4 miles.
I had been too busy working and giving my time to the company. But lucky to hit paper?? Ugh.
I reloaded, and immediately was making all shots within an eight inch diameter circle.
Then all shots at a 1/4 mile within the diameter of a quarter, a 25 cent piece.
If you want the data I forgot, send me a message.
And the best of it, my wife of 4+ decades has been on board from the beginning. She did get herself a new rifle at the same time.
Have fun, shoot straight, make the first shot count.
Be safe and have too much fun!
Edit: I use cartridges without powder that I place in my practice stack at my desert place. They are either attached to my belly, temperature control, or in the shade. I fill the magazines, then set aside as I mix them up. No idea which has blanks, and which all live rounds. I do the same with my pistol rounds.
If it does not go boom, the bolt is removed, and I look thru the barrel. I carry a couple of long brass rods, just in case I get a primer fired slug.
One time the brass swelled up. That was the end of my .338 LM shooting that week.
Keep your rounds attached to your belly, 98.6℉, which is a lot lower than 120℉ plus whatever the desert oven makes them. Repeatability and consistency make for stable shooting.
I find that if I do not shoot for too long, I begin to wince, react before the Bang, and just turn into a kid shooing his first rifle.
I talk too much.
HAVE FUN!