I’ve been thinking about when it becomes unethical to use a given round/BC beyond a given range. For example, at what point does .223 become spray and pray? And does it depend on skill, type of target (commercial range, hunting, combat), conditions (wind, rain, light) or other factors? If so, I doubt there’s much agreement as to the maximum range at which a given round should be used, because people start out with different assumptions. But I’ll ask specifically for a beginner in a PRS match shooting at metal targets out to 1200 yards on a commercial range in decent conditions, would it possibly be unethical to use a .223 beyond a certain range? What about a gas gun match out to 700 yards max? Is there a level of wind or other conditions at which the beginner should drop out of the match or decline to shoot at targets beyond a certain range? Thanks.
Addressing your question directly...
.223 in a 20" gas gun (though, let's be frank, the AR is the only accessible one accurate enough to bother with) is pretty effective at 900-1,000 yards if it was set up carefully to BE effective. That last 100 yards is a bitch of a walk though, even if it is setup well. If you had a 26" tube, that is WORLDS different, because at that range, every 25 fps is CRITICAL.
The other thing most guys won't agree to do is load singly, with 90's, and a barrel and chamber specifically for it.
Facts
--If you want to shoot an AR from magazine, then 700, or maybe 800 yards, is gonna be about it.
--If you want to have a "tactical" AR with anything less than a 20" tube [like God intended], then maybe 600 yards is about it, or way less.
--If you dislike the idea of spec'ing out an upper and sourcing a barrel that's going to be in the $1,500 range, then maybe 500 yards is it.
--If you shoot mostly bolt guns and your shotty, and plan to just stroll out there with a new AR and shoot 3/4 Minute groups, well...good luck with that. They don't drive the same way.
--If you think using high-quality load components (Lapua, Sierra, JLK, Berger, et al.) is a waste in an AR, then anything beyond 300 yards is not for you, and just assume that all AR's are 3/4 Minute or worse, because you'll never see the light.
Now for BOLT rifles with 26-30" barrels, I don;t know that you gain THAT much long range precision with them, but I do know that it's way easier to get them to shoot well, and you gain a LOT of speed. In certain areas, the .223 "ELR" rifle would probably be pretty effective to 1,200 yards, more if you have a bullet that will transition.
-Nate