7.62x39: Improving the Military Standard

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With an optic to replace the AK's terrible iron sights, this shooter engages targets out to 425 yards; his ammunition needs to be accurate enough to get the job done.

With these characteristics in mind, 7.62x39 is a good platform for launching medium and heavy .30 caliber projectiles at a somewhat sedate velocity. The standard loading of a 123-grain bullet at 2330 fps represents what I believe ought to be the lower end of bullet mass used with 7.62x39. In this bullet-weight class, terminal performance can be improved simply with the use of better bullets.

Unlike virtually all other "7.62" or .30 caliber cartridges, the Russian 7.62x39 uses a non-standard bullet diameter: .310 inch instead of .30. Thus most "Western" .30 caliber or .308 bullets will not work in the 7.62x39. This is slowly changing as a a few bullet makers have come forth with modern bullets specifically for the 7.62x39.

The most interesting is the 123-grain Barnes TSX-BT. Barnes' TSX bullets are made from solid copper; they do not have a conventional jacket and core. The TSX bullet has a solid shank, and then a hollow-point nose. When the bullet impacts tissue, the hollow point expands to create a wide wound channel while the solid bottom shank stays solid for excellent penetration. The TSX-BT bullet has a boat-tail to incrementally aid the BC value. Barnes TSX bullets have yielded impressive results on game from .22 caliber up to .33 caliber.

Standard lead-tipped hunting bullets such as the Hornady 123-grain SP will produce predictable results on game. Lapua has a 123-grain FMJ bullet that ought to produce terminal results about the same as the mil-spec FMJ. Standard construction hollow-point bullets will produce more violent expansion and fragmentation, usually at the expense of overall penetration. Cor-Bon's 125-gr JHP and the Wolf "Military Classic" JHP both will provide increased terminal performance over standard FMJ. The Wolf JHP shows fragmentation in ballistic gelatin.

Regular .30 caliber bullets are not proper for 7.62x39; Barnes, Hornady, and Lapua are three manufacturers with bullets specifically for the Russian cartridge.

Here are potential untapped strengths of the 7.62x39. First, because of the relatively small powder volume versus bore size, relatively little performance is lost as barrel length is reduced. This makes the 7.62x39 a perfect candidate for very short carbines. For example, a load that replicates M43 using Accurate #1680 powder will lose only about 70 fps when barrel length is reduced from 16 inches to 14 inches. Going down to a 12-inch barrel only loses another 83 fps, while a 10.5 inch barrel will still fire the 123-grain bullet at just over 2100 fps. The 7.62x39 is an ideal cartridge for a short-barreled rifle, provided a bullet that produces good terminal ballistics is used.

The second untapped strength of 7.62x39 is the use of heavier bullets. Although the vast majority of loads use a 120 to 125-grain bullet, a 150-grain bullet - the mainstay of .308 Winchester loads - can be fired at 2100 to 2200 fps from a 16-inch barrel. Going further, a 175 to 180-grain bullet can be fired at 1900 to 2000 fps. As bullet mass is increased, the ability for impressive penetration and terminal effects improves. These heavy bullets will lose even less velocity as barrel length is reduced. For example, a 180 grain load may lose only 100 fps as the barrel length is reduced from 16 to 12 inches.

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This article has 4 pages. You're on page 3.