.223 Remington

.223 Remington
A variety of .223 Remington cartridges with a .308 Winchester (right) for comparison
TypeRifle
Place of originUnited States
Production history
DesignerRemington Arms
Designed1962
Produced1964–present
Variants5.56×45mm NATO
Specifications
Parent case.222 Remington
Case typeRimless, bottleneck
Bullet diameter.2245 in (5.70 mm)
Land diameter.219 in (5.56 mm)
Neck diameter.253 in (6.43 mm)
Shoulder diameter.3542 in (9.00 mm)
Base diameter.3759 in (9.55 mm)
Rim diameter.378 in (9.60 mm)
Rim thickness.045 in (1.14 mm)
Case length1.760 in (44.70 mm)
Overall length2.260 in (57.40 mm)
Case capacity28.8 grain H2O (1.87 ml)
Rifling twist1 in 12 in (305 mm) (military-style rifles use 1 in 7 in (178 mm) to 1 in 10 in (254 mm) to stabilize longer bullets)
Primer typeSmall rifle
Maximum pressure (SAAMI)55,000 psi (380 MPa)
Maximum pressure (CIP)62,366 psi (430.00 MPa)
Maximum CUP52000 CUP
Ballistic performance
Bullet mass/type Velocity Energy
36 gr (2 g) JHP 3,750 ft/s (1,140 m/s) 959 ft⋅lbf (1,300 J)
55 gr (4 g) Nosler ballistic tip 3,240 ft/s (990 m/s) 1,265 ft⋅lbf (1,715 J)
60 gr (4 g) Nosler partition 3,160 ft/s (960 m/s) 1,325 ft⋅lbf (1,796 J)
69 gr (4 g) BTHP 2,950 ft/s (900 m/s) 1,338 ft⋅lbf (1,814 J)
77 gr (5 g) BTHP 2,750 ft/s (840 m/s) 1,301 ft⋅lbf (1,764 J)
Test barrel length: 24 inches (61 cm)
Source(s):

The .223 Remington designated 223 Remington by SAAMI and 223 Rem. by the C.I.P., (pronounced "two-two-three") is a rimless, bottlenecked, centerfire intermediate cartridge. It was developed in 1957 by Remington Arms and Fairchild Industries for the U.S. Continental Army Command of the United States Army as part of a project to create a small-caliber, high-velocity firearm. The .223 Remington is considered one of the most popular common-use cartridges and is used by a wide range of semi-automatic and manual-action rifles.