A series of introductory articles conceived to teach beginners specs, features and history of the most popular rifle ammunition calibers
Up until very recent times, the 7,62x51mm or .308 Winchester caliber was the world's most popular military service round; it represented the first attempt to reduce the U.S. service .30-06 Springfield cartridge to a more compact size, but unlike what the Soviets did with the 7,62x39mm caliber − and unlike what the Germans did before that with the 8x33mm "Kurz" cartridge − the U.S. didn't fully embrace the intermediate cartridge philosophy: what they did was to merely shorten the .30-06 round a little bit while retaining more or less its original performance levels.
Some history
The debut of the .308 Winchester ammunition was somewhat unique for being a military cartridge, in that it wasn't developed in a military arsenal and was offered for civilian sales before the military would show any interest about it.
The Frankford Arsenal had been trying to shorten the .30-06 Springfield round for quite some time, but the process was slow-paced and had been returning meager results; it didn't take much for the Winchester Ammunition company to fully understand the potential of this caliber, launching it commercially in 1952.
The evolution in quality of propellant powder mixtures allowed this new round to offer basically the same performance of the old .30-06 Springfield cartridge despite the more compact dimensions; the U.S. military was immediately appealed by the new Winchester .308 caliber, and it was adopted in 1953 as the "U.S., Ball Cartridge, T65".
It was immediately well received by military users and civilian customers alike, and became appreciated and successful basically in any field of application.
Military operators found the 7,62x51mm/.308 Winchester to be an excellent caliber, more compact than .30-06 Springfield and, unlike it, well controllable when used in full-auto mode on general-purposes machineguns, as well as extremely accurate on individual infantry weapons and less prone to jammings, as its shorter case allows its use in firearm designs based on a short-travel bolt.
The cartridge
On the civilian market, basically every gunmaker started to produce rifles and carbines chambered for the .308 caliber very soon after its introduction; it also debuted on lever-action rifles, a type of firearms which is extremely popular on the U.S. market but less than adequate to this kind of ammunition.
Bench-Rest sport shooters were soon greatly impressed by the high level of intrinsic accuracy of this caliber − quite possibly its best known quality − and by the fact that it could be further improved by well-calculated hand loads; this also contributed to turn .308 Winchester / 7,62x51mm into the most popular caliber in long-range precision shooting sports − a position it held for years, before several specific chamberings were launched on the market.
The .308 / 7,62x51mm caliber is also one of the backbones of the ammunition market, with basically all manufacturers offering a plethora of variants, both by quantity and quality, although precision shooting loads are generally preferred. The reloading components industry is likewise highly engaged in the manufacture of .30-caliber dedicated supplies, most notably offering balls in any and all sizes and weights, and for any purpose.
Fields of use
The .308 Winchester / 7,62x51mm is a great big game hunting round, albeit not just as versatile as its forerunner, the .30-06 Springfield round; its compact size, good power and excellent accuracy make it a perfect choice on any mid-to-big size prey, and most of all, make it suitable for use on short-action rifles and carbines.
Oddly enough, it is not a popular choice for battue hog hunt, at least in Europe; it would indeed be more apt for the role than the above-mentioned .30-06 Springfield, but at the same time it's more popular than the latter in selective hunting and target shooting specialties. The .308 Winchester / 7,62x51mm caliber is best loaded with bullets ranging between 150 and 165 grains in weight, but 180-grains loads remain well manageable despite being at the edge of this caliber's limits; some users still find it proficient even with 200-grains balls.
It is extremely easy to reload; hand reloading can indeed boost the intrinsic potential of .308/7,62mm, allowing the preparation of extremely high accurate and versatile loads offering performance levels that are mostly unthinkable for calibers other than .30 − more than enough to stalk the most popular mid-sized and heavy game available in Europe. Its trajectory is not exactly the flattest, but drop compensation becomes very easy with little practice even when taking the most difficult shots. Recoil is very controllable and won't scare the shooter, allowing him or her to focus on the target rathern than on the recoil energy.
Curiosities
Military surplus ammunition or spent cases for this caliber are very easy to find on the market, but their use is not indicated for anything much than training at the range, and military surplus spent cases may be less than ideal to use for the hand loading of hunting-oriented rounds: they're harder, thicker and sturdier, and thus heavier; they also provide a lower propellant capacity. The weight of cases should always be checked before reloading and compared with the weight of commercial cases; some times it may be necessary to reduce the propellant quantity of about 10%.
The U.S. Armed Forces replaced the .308 Winchester / 7,62x51mm round in general issue with the new 5,56x45mm / .223 Remington round when the Department of Defense decided to fully embrace the "intermediate cartridge" philosophy for individual infantry weapons, in 1964. 7,62x51mm still remains in service for several purposes, and is making a comeback in roles from which it has been phased out due to the resparked demand for increased range, accuracy, penetration and stopping power in certain situations on the modern theatres of operation.
The 7,62x51mm / .308 Winchester caliber is also known as 7,62x51 NATO, .30 NATO, .30 OTAN or 7,62mm NATO.
A minority of historians trace the origins of the .308 Winchester round back to the Italian 7,35x51mm Carcano cartridge rather than to .30-06 Springfield, maybe due to the overall case lenght.
An example of reloading specs for the .308 Winchester / 7,62x51mm cartridge
| Gun: Remington 700 Police | Barrel lenght: 66 centimeters |
Caliber | Propellant | Quantity | Bullet | Primer |
.308 Winchester - 7,62x51mm | Vihtavuori N140 | 42,5 grains | Palla Lapua Match 168 grains | CCI Standard |
An example of reloading specs for the .308 Winchester / 7,62x51mm cartridge
| Gun: Remington 700 VTR | Barrel lenght: 54 centimeters |
Caliber | Propellant | Quantity | Bullet | Primer |
.308 Winchester - 7,62x51mm | Vihtavuori N140 | 48 grains | Barnes TSX 150 grains | Remington Standard |
An example of reloading specs for the .308 Winchester / 7,62x51mm cartridge
| Gun: Remington 7400 semi-automatic rifle | Barrel lenght: 54 centimeters |
Caliber | Propellant | Quantity | Bullet | Primer |
.308 Winchester - 7,62x51mm | Vihtavuori N140 | 47 grains | RWS KS 150 grains | CCI Standard |
.308 Winchester - 7,62x51mm | Winchester 748 | 46,5 grains | Sierra BT 150 grains | Federal 215 |
.308 Winchester - 7,62x51mm | IMR 4350 | 51 grains | Remington Spitz. 165 grains | CCI Standard |
| .308 Winchester - 7,62x51mm | Norma 201 | 39 grains | RWS H Mantel 180 grains | CCI Standard |
| .308 Winchester - 7,62x51mm | Vihtavuori N140 | 44 grains | Nosler Partition 180 grains | CCI Standard |
Warning:
Our readers should be advised that ammunition handloading requires skill and attention. All provided handloading data should be considered as purely indicatory; even the slightest variations could cause dangerous pressure surges, which could in turn result into bodily harm or property damage. In no case will the author of this article or all4shooters.com accept any responsibility for any injury or damage caused by the improper use of these data.
