308 x 1.5" Barnes

Historical Notes:

The 308 x 1.5 inch was developed by Frank C. Barnes in March of 1961. It is based on the 308 Winchester case shortened from the original 2.01 inches to a length of 1.5 inches. The only other difference is in the shoulder diameter which is .003 inch larger than the original cartridge. Two rifles were made up for the developmental work. One a Swedish Model 96 short military bolt action (1 in 12 inch twist) by Les Corbet, and the other on a Remington rolling block single shot action (1 in 10 inch twist) by P.O. Ackley. Both rifles proved to be extremely accurate although the 1 in 12 inch twist appears to be the one that has become more or less standard for this cartridge. The 308 x 1.5 inch is similar to the 7.62 x 39mm Russian (M43) military round, but is larger in base diameter and has a greater powder capacity. Consequently, it can be loaded to produce higher velocity with any given bullet weight. At the time the cartridge was introduced, several gun designers, working on assault rifle designs they hoped to sell to the government, chambered their weapons to handle the 308 x 1.5 inch. However, nothing came of these efforts, and the cartridge has never been seriously considered as a military round. A number of individual experimenters have worked with variations of the original 308 x 1.5 inch Barnes case configuration by lengthening it to 1.6 inch, 1.7 inch, etc., and it has been necked down to 22, 6mm, and 7mm caliber and necked up to 375. The case capacity of the 308 x 1.5 inch is close to that of the 223 Remington, and if necked down to 22 caliber, it delivers approximately the same ballistics. The original case forming dies were made by RCBS and these can still be ordered as a regular stock item.

General Comments:

As originally conceived, the 308 x 1.5 inch was envisioned as a varmint through deer class sporting cartridge that could be chambered in very lightweight, short action rifles for hunting under conditions where reduced bulk and heft would be at a premium. As a secondary possibility, it could provide a very efficient 30 caliber match or even a benchrest cartridge. However, it has emerged as more of a special purpose handgun cartridge for use in custom single shot pistols for silhouette shooting. Many custom barrels have been made for the popular Thompson/Center Contender single shot pistol in 308 x 1.5 inch caliber, and in addition, the Wichita Silhouette Pistol, made by Wichita Engineering and Supply Inc. of Wichita, Kansas, offers it as a standard caliber. Also a number of custom pistolsmiths who make up single shot pistols based on the Remington XP-100 bolt action offer it as a caliber of choice.

As a rifle cartridge, the 308 x 1.5 inch delivers initial velocities in excess of the factory loaded 30-30 Winchester ( A true 2530 fps to 2540 fps with the 150 grain bullet as opposed to the advertised 2410 fps of the commercial 30-30). Actually, as demonstrated through chronograph tests, the factory 150 grain loading of the 30-30 develops only about 2250 fps from a 22 inch barrel and most 30-30's sold have 20 inch barrels. Since the 308 x 1.5 inch is used exclusively in bolt or single shot actions, this allows the use of spitzer bullets, which means that the retained velocity at the longer ranges will also be greater than the flat pointed 30-30 bullet. Properly loaded, it has good killing power on animals up to deer size at ranges out to about 150 yards or so.

Small cartridges such as the 308 x 1.5 inch are very efficient and deliver performance out of all proportion to their size. However this is only achieved at relatively high pressure levels of around 50,000 to 52,000 psi. Commercial 30-30 ammunition, by comparison, is not loaded to over about 40,000 psi. When loading the 308 x 1.5 inch, or any similar cartridges, to maximum performance levels, only a few tenths of a grain of powder can run pressure up to unsafe pressure levels. Also, if military brass is used for forming cases, all maximum charges must be reduced because the heavier brass reduces the case capacity and increases the loading density, thereby increasing pressure. A number of shooters have been using the 308 x 1.5 inch for shooting cast bullets. Lou Delgado of Thousand Oak, California, has been experimenting with cast bullets and various twists from 1 in 12 inches through 1 in 16 inches.

Source: Cartridges of the World

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