.308×1.5-inch Barnes

The .308×1.5" Barnes is a wildcat cartridge based on the .308 Winchester (7.62×51mm NATO). The cartridge is similar to the 7.62×39mm Russian (M43) cartridge though it outperforms the Soviet cartridge. It was designed by Frank C. Barnes in March 1961 by shortening the .308 Winchester to 1.5 in (38 mm) and giving it a shoulder angle of 20° (α=40°) similar to the parent cartridge.

.308×1.5" Barnes
Type	Rifle
Place of origin	USA
Production history
Designer	Frank Barnes
Designed	1961
Variants	.30 BR
Specifications
Parent case	.308 Winchester (7.62×51mm NATO)
Case type	Rimless bottlenecked
Bullet diameter	.308
Neck diameter	.338
Shoulder diameter	.450
Base diameter	.466
Rim diameter	.470
Rim thickness	.048
Case length	1.500
Overall length	2.05 in (52 mm)
Case capacity	38.0 gr H2O (2.46 cm3)
Rifling twist	12
Primer type	Large rifle
Maximum pressure	Approximately 60,000 psi (4,100 bar)
Ballistic performance
Bullet mass/type Velocity Energy 150 gr (10 g) spitzer 2,500 ft/s (760 m/s) 2,082 ft⋅lbf (2,823 J)

History

The first rifles commissioned for the developmental work by Barnes for the .308×1.5" cartridge were a Swedish Model 96 Mauser with a 1 in 12 (305 mm) twist built by Les Corbet and a Remington Rolling Block with a 1 in 10 (254 mm) twist built by P.O. Ackley. Due to the weights of the bullet and the performance of the cartridge, the 1 in 12 twist became the standard by consensus.

Similar cartridges

Apart from experimenting with .308×1.75", the legacy of the Barnes cartridge is found in its progeny cartridges. The .308×1.5" caused a wildcatting craze, which had individuals necking the cartridge down to .224 (5.56 mm), .243 (6 mm), .264 (6.5 mm), .284 (7 mm) and necking up to .338 (8.5 mm) and .375 (9.5 mm). Due to the cartridges’ efficiency and accuracy, many of these cartridges, such as the .22 BR, 6mm BR, 6mm BR Norma, 7mm BR, and .30 BR, went on to become popular benchrest cartridges and some of these were adopted by mainstream ammunition manufacturers. The .308×1.5" was one of the original short fat cartridge designs, having a length to width ratio of 3.17. The short fat cartridge design is considered to promote efficiency and shot to shot consistency.

The .308×1.5" Barnes cartridge is comparable to cartridges such as the 7.62×39mm and the .30-30 Winchester. The .308×1.5" is capable of launching a 150 gr (9.7 g) bullet at 2,500 ft/s (760 m/s). While the Barnes and 7.62×39 are similar length, the Barnes has a greater body girth, which provides a greater propellant capacity which in turn contributes to its performance advantage. While the .30-30 Winchester has about a 16% greater capacity over the Barnes cartridge, the .30-30 has a SAAMI-recommended pressure limit of 42,000 psi (2,900 bar). For this reason, most factory .30-30 ammunition loaded with a 150 gr (9.7 g) bullet achieves a mere 2,390 ft/s (730 m/s). Furthermore, the Barnes cartridge is capable of launching heavier bullets than the 7.62×39 and has the advantage of using spitzer bullets and is chambered in strong bolt-action rifles, whereas the .30-30 is commonly loaded with round-nose or flat-nose bullets due to the fact that it is chambered in lever-action rifles with tubular magazines.

The .308×1.5" Barnes was intended as a short range deer cartridge that could also be used as a varmint and predator cartridge. Loaded with the 150 gr (9.7 g) cartridge, it is capable of taking deer-sized game out to 150 yd (140 m). For predator and varmint hunting, bullets weighing 90–125 gr (5.8–8.1 g) are commonly used.

Further reading

• De Haas, Frank (2003). Bolt Action Rifles - 4th Edition.
• Donnelly, John J. (1987). The Handloader's Manual of Cartridge Conversions.
• Howell, Ken (1995). Designing and Forming Custom Cartridges.
• Barnes, Frank C. (1997) [1965]. McPherson, M.L. (ed.). Cartridges of the World (8th ed.).