Originally Posted by Nomercy448

Wasn't going to push the .223rem/5.56N as a recommendation. Not making any comment about my beliefs on the .223rem effectiveness on deer in general, but for a young hunter that might not have the best trigger control, shot placement, etc I'm not one to recommend the .223rem.

Which isn't to say there aren't other cartridge options in the AR-15 platform, a 6.8SPC AR-15 would make a FANTASTIC youth deer rifle cartridge (or adult for that matter). But again, all of the other reasons that it's not an ideal choice still apply. Even a 16" M4 carbine with a scope can end up in the 8-9lb range (mine is 11lbs including the bipod).