[Mariner]

It’s THE round that should be in the AR-15.

It would make all the difference, and resolve all complaints.

[Mouton]

I love my .243 Browning.

I tried to find a decently priced AR in 243 cal.

My favorite round is the federal 100gr SP. Relatively cheap but lethal.

[Charles Martel]

It’s THE round that should be in the AR-15.

It'd have to be the AR-10, due to the magazine well dimensions of the AR-15 being too small for the .243 - and some manufacturers do offer AR-10 clones in .243. Nice caliber; my first "bought it myself" deer rifle was a Remington 788 in .243. It put lots of venison in the freezer - still does, on occasion.

[Trailerpark Badass]

Won’t fit.