I have a soft spot for the 243. shot my first deer with it and thats all dad has ever used. I have shot and seen deer shot with the 243, and some just seem the run farther double lunged than my bigger rounds. MY sis in law just shot her first deer a whitetail doe this fall with my tikka t3 lite in 243 pushing a 90 gr speer deep curl(think fed fusion), 3100 fps. 100 yards. she thought she missed cause it ran 60 yards to the bush and gone. I found good blood and we found the doe 100 yards from where it was shot. Could walk along the blood trail at a decent pace. massive holes in top rear of lungs. seen 1 other deer, 320 yards quartering away go about 120 yards with that same combo. definite expansion, bullet went in last rib and came to rest offside shoulder. beautiful mushroom, 60% weight retention. all other 243 deer didnt make it past 50.
As to barrel life i have personally shot out a 243 i bought new in 1300 rounds. heavy barrel savage used it as a long range fun rig for years. Barrel cleaned every 50 rounds. Wipeout so no brushes. Still held half moa at 800 yards at the 1000 round mark. at 1300 it shot 6 feet groups at 800, 2 feet at 600, however 400 was still moa. throat was gone, no rifling for the first .75 inch and very faint for the next .75. got it warm on occasion, 10 shot strings, then cool off. it got replaced with a 6.5 creed. barrel life on them is about 2500-3000 as a long range rig.
i am looking for a short stocked rifle for my wife, 243 and 6.5 creed are my first pick, cause i have dies, 7mm08 also in there.