army,
Having a room of my own is more important to me nowadays than it was as a kid.
Mine is about like yours.
One suggestion, your USA flag, the stars belong in upper left corner when displayed.
Doesn't matter hanging horizontal or vertical.
dk
I did a little guessing since rifle weight and bullet speed wasn't given.
I assumed 9 lbs and 3500fps for the 240 WBY & 11 lbs and 2650 fps for the 308 WIN.
My program gave the following.
240 WBY 8.3 ft/lbs recoil at 7.7 fps
308 WIN 11.8 ft/lbs at 8.3fps
So the answer is the 308...
I built a 338 Federal on a long action Savage.
It started out a 25-06.
No changes to the magazine or follower.
It feeds smooth and positive.
That's as close as I can get.
dk
I've been using them for a couple of years now.
Tried several different models (all diy) and settled on the SuperCat.
Regular denatured alcohol from the hardware store seems to be the best all around fuel.
Light weight and dependable.
Be sure to practice at home first as they're different...
It also depends on how the rifle fits you.
I own 2 300wm chambered rifles.
My Weatherby sporter is a joy to shoot.
My Savage heavy barrel is a pain, for me.
It's the opposite for my son.
dk
Maybe you caught this, maybe not.
The last thing he 'said' tells me (and should you) he doesn't know Savage rifles as well as he should.
It's not a matter of extractors.
You need to change bolts or swap bolt heads.
He looses all credibility & causes me to wonder...
Was he just fishin' for...