Might want to look at Hornady Light Magnum ammo
With a light hitter like .243 I think the extra 200 FPS will add some need knockdown power. They are available in 85 & 100 gr SP and SST.
I use the Light Mag 150 Gr in my .308 and get .300 mag-type performance.
I have also tested Remington, Federal, Winchester, in most of their permutations and have found no more accurate factory ammo.
Oh yes, I forgot IMHO.