Okay I had to look it up... And I always qualified as expert in the Army... You think I'd remember this stuff....
Depending on who you believe.... the mathematician or the bullet manufacturer or the range officer....
The 5.56 shot out of a 16" barrel has a maximum effective range of 463 meters (500 yards). Effective range is the range at which more than 50% of the shooters can hit the target more than 50% of the time using iron sights.
Some marines and foreign armies will train at 800 yards.
I've done 500... 800 is a LOT farther when you get right down to it....
The maximum distance the bullet will travel is somewhere around 4,000 yards (of course you'd be shooting at about a 45* angle and it will only have terminal velocity on impact, but could still be quite deadly). There are many charts out there showing .223 bullets can travel 3 miles which is 5,000 yards, but I'm sure conditions will effect this number greatly.
So I'll retract my initial statement or
clarify it anyway, the effective range of an AR-15 is 500 yards using the military definition of effective, and it can be lethal and accurate to 800 yards and well beyond.
If you tell a marine sniper he can't hit a target at 1,000 yards with an AR I will put my money on him proving you wrong.
