.308 Winchester

.308 Winchester
From left to right 9.3x62mm, .30-06 Springfield, 8x57mm IS, 6.5x55mm and .308 Winchester cartridges. The 7.62x51mm NATO is similar in appearance to the .308 Winchester.
Type	Rifle
Country of Origin	USA
Specifications
Parent Case	.300 Savage
Case Type	Rimless, Bottleneck
Bullet Ø	0.308 in (7.8 mm)
Neck Ø	0.343 in (8.7 mm)
Shoulder Ø	0.454 in (11.5 mm)
Base Ø	0.470 in (11.9 mm)
Rim Ø	0.473 in (12.0 mm)
Rim Thickness	0.050 in (1.3 mm)
Case Length	2.015 in (51.2 mm)
Full Length	2.800 in (71.1 mm)
Rifling twist	1/12
Primer	Large Rifle
Production & Service
Design Date	1952
Production Dates	1954-present
Ballistic Performance Sampling
Bullet Wt./type Velocity Energy 150 Nosler tip 2820 2648 165 BTSP 2700 2671 168 BTHP 2650 2619 175 BTHP 2600 2627 180 Nosler partition High-Energy 2740 3000 Test barrel length: 24 in Source: Federal Cartridge Co. ballistics page

.308 Winchester is the commercial name of a centerfire cartridge based on the military 7.62x51mm NATO round. Two years prior to the NATO adoption of the 7.62x51mm NATO T65 in 1954, Winchester (a subsidiary of the Olin Corporation) branded the cartridge and introduced it to the commercial hunting market as the .308 Winchester. Winchester's Model 70 and Model 88 rifles were subsequently chambered for the new cartridge. Since then, the .308 Winchester has become the most popular short-action big-game hunting cartridge worldwide. It is also commonly used for civilian targets, military sniping and police sharpshooting. The relatively short case makes the .308 Winchester especially well adapted for short action rifles.

Among calibers larger than 6mm, the .308 is by far the most popular short-action big-game cartridge among hunters worldwide.

Cartridge dimensions

The .308 Winchester has 3.64 ml (56.0 grains) H₂O cartridge case capacity. The exterior shape of the case was designed to promote reliable case feeding and extraction in bolt action rifles and machine guns alike, under extreme conditions.

.308 Winchester maximum C.I.P. cartridge dimensions. All sizes in millimeters (mm).

Americans would define the shoulder angle at alpha/2 = 20 degrees. The common rifling twist rate for this cartridge is 305 mm (1 in 12 in), 4 grooves, Ø lands = 7.62 mm, Ø grooves = 7.82 mm, land width = 4.47 mm and the primer type is large rifle.

According to the official C.I.P. (Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives) guidelines the .308 Winchester case can handle up to 415 MPa (60,190 psi) piezo pressure. In C.I.P. regulated countries every rifle cartridge combo has to be proofed at 125% of this maximum C.I.P. pressure to certify for sale to consumers.

The .308 Winchester and 7.62x51mm cartridges are not identical and there are minor differences in their inner case dimensions, though SAAMI does not list either cartridge as unsafe in a firearm designed for use with the other.

The .308 Winchester as a parent case

Several more cartridges have been developed using the .308 Winchester as a parent case, some becoming very popular for hunting, particularly in North America. These are the .243 Winchester, the .260 Remington (aka 6.5-08 A-Square), the 7mm-08 Remington, the .338 Federal, and the .358 Winchester (aka 8.8x51mm). In 1980, two rimmed cartridges based on the .308 Winchester were introduced for use in the Winchester Model 94 XTR Angle Eject rifle; the .307 Winchester and the .356 Winchester.

References

• C.I.P. decisions, texts and tables (free current C.I.P. CD-ROM version download (ZIP and RAR format))

See also

• List of firearms
• List of rifle cartridges
• Hydrostatic shock
• Delta L problem

External links

• .308 Winchester Cartridge Guide by AccurateShooter.com
• .308 Videos by StoppingPower.Info