Terminal Ballistics of the 5.56 NATO

Gabriel Suarez (1999 p. 39) provides data on the terminal ballistics of the 5.56 NATO ball ammunition (M193) for both the 20” AR-15 barrel and the 14” to 16” CAR-15 barrel.

Terminal Performance Velocity 20” barrel 14” to 16” barrel
Flips over, breaks at cannelure, base shatters into many pieces.
Over 2700 fps 0 to 150 yards 0 to 75 yards
Flips over, bends or breaks at cannelure, but with no fragmentation.
2500 to 2700 fps 150 to 200 yards 75 to 150 yards
Does not flip over or bend at cannelure; similar to the .22 WMR cartridge.
Below 2500 fps 200 yards or more 150 yards or more

This is considerably less optimistic than the data provided by Charlie Cutshaw, who expects peak performance at any velocity over 2400 fps, which extends the effective range out to 200 meters (219 yards). Since Suarez cites the U.S. Army Wound Ballistics Lab, his data is probably more accurate than that of Cutshaw, who does not cite his sources. But it also depends greatly on how heavy the person’s clothing is and how fat they are.

Skinny Afghans in bulky wool overcoats may be immune to the CAR-15 at anything but point-blank ranges while fat Americans in t-shirts can be knocked flat at 300 yards with a heavy-barrel AR-15. Psychology is also important; people who watch a lot of TV tend to fall down when shot because that is what movie actors do while people with no pre-conceived expectations just wince and then continue fighting when struck a light blow. But even this very optimistic 300-yard estimate is still only a third of the fantastic 900-yard range that the GPS Defense Sniper School teaches.

With its weak cartridge (to minimize recoil when firing rapidly) and its high sights (to limit muzzle rise when firing offhand), the AR-15 is an excellent assault rifle. It is NOT a sniper rifle, even with a heavy barrel. Trying to turn an assault rifle into a sniper rifle is a fool’s errand.

Note that Suarez advocates the use of soft-point hunting bullets for users of the 14” to 16” CAR-15. These just expand without any flipping over or shattering but, since you are not going to get that effect beyond 75 yards anyway, you can at least get some expansion.

Suarez, Gabriel. 1999. The Tactical Rifle. Boulder, CO: Paladin Press