| .30-06 Springfield | ||
|---|---|---|
.30-06 Springfield cartridge with soft tip |
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| Type | Rifle | |
| Place of origin | United States | |
| Service history | ||
| In service | 1906–present | |
| Used by | USA and others | |
| Wars | World War I, World War II, Korean War, Vietnam War, to present | |
| Production history | ||
| Designer | United States Military | |
| Designed | 1906 | |
| Produced | 1906–present | |
| Specifications | ||
| Parent case | .30-03 Springfield | |
| Case type | Rimless, bottleneck | |
| Bullet diameter | .308 in (7.8 mm) | |
| Neck diameter | .340 in (8.6 mm) | |
| Shoulder diameter | .441 in (11.2 mm) | |
| Base diameter | .471 in (12.0 mm) | |
| Rim diameter | .473 in (12.0 mm) | |
| Rim thickness | .049 in (1.2 mm) | |
| Case length | 2.494 in (63.3 mm) | |
| Overall length | 3.34 in (85 mm) | |
| Case capacity | 68 gr H2O (4.42 cm³) | |
| Rifling twist | 1-10 in. | |
| Primer type | Large Rifle | |
| Maximum pressure | 60,200 psi | |
| Ballistic performance | ||
| Bullet weight/type | Velocity | Energy |
| 150 gr (9.7 g) Nosler Ballistic Tip | 2,910 ft/s (890 m/s) | 2,820 ft·lbf (3,820 J) |
| 165 gr (10.7 g) BTSP | 2,800 ft/s (850 m/s) | 2,872 ft·lbf (3,894 J) |
| 180 gr (12 g) Core-Lokt Soft Point | 2,700 ft/s (820 m/s) | 2,913 ft·lbf (3,949 J) |
| 200 gr (13 g) Partition | 2,569 ft/s (783 m/s) | 2,932 ft·lbf (3,975 J) |
| 220 gr (14 g) RN | 2,500 ft/s (760 m/s) | 2,981 ft·lbf (4,042 J) |
| Test barrel length: 24 inch 60 cm Source(s): Federal Cartridge[1] / Accurate Powder[2] |
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The .30-06 Springfield cartridge (pronounced “thirty-aught-six”, "thirty-oh-six") or 7.62×63mm in metric notation, was introduced to the United States Army in 1906 and standardized, and was in use until the 1960s and early 1970s. It replaced the .30-03, 6 mm Lee Navy, and .30 US Army (also called .30-40 Krag). The .30-06 remained the US Army's primary rifle cartridge for nearly 50 years before it was replaced by the 7.62×51mm NATO (commercial .308 Winchester) and 5.56×45mm NATO (commercial .223 Remington), both of which remain in current U.S. and NATO service. It remains a very popular sporting round, with ammunition produced by all major manufacturers.
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Much of the rest of the world at the turn of the 20th century was in the process of adopting the pointed spitzer bullet: France in 1898, Germany in 1905, Russia in 1908, and Britain in 1910,[3] so when it was introduced, the .30-03 was behind the times. A new case was developed with a slightly shorter neck to fire a higher velocity, 150-grain (9.7 g) spitzer bullet at 2,700 ft/s (820 m/s). The M1903 Springfield rifle, introduced alongside the earlier cartridge, was quickly modified to accept the .30-06 cartridge, known as the M1906. Modifications to the rifle included shortening the barrel at its breech and recutting the chamber. This was so that the shorter ogive of the new bullet would not have to jump too far to reach the rifling. Other changes included elimination of the troublesome 'rod bayonet' of the earlier Springfield rifles. Experience gained in World War I indicated that other nations' machine guns far outclassed American ones in maximum effective range. Additionally, before the widespread employment of light mortars and artillery, long-range machine gun 'barrage' or indirect fires were considered important in U.S. infantry tactics.[4] For these reasons, in 1926, the Ordnance Corps developed the .30 M1 Ball cartridge using a 174-grain (11.3 g) bullet with a 9 degree boat tail, traveling at a reduced muzzle velocity of 2,640 ft/s (800 m/s). This bullet offered significantly greater range from machine guns and rifles alike due to its increased ballistic coefficient. Additionally, a gilding metal jacket was developed that all but eliminated the metal fouling that plagued the earlier cartridge. Wartime surplus totaled over 2 billion rounds of ammunition. Army regulations called for training use of the oldest ammunition first. As a result, the older .30-06 ammunition was expended for training; stocks of M1 ammunition were allowed to slowly grow until all of the older ammo had been fired. By 1936 it was discovered that the maximum range of the new M1 ammunition and its 174-grain (11.3 g), boat-tailed bullets were beyond the safety limitations of many ranges. An emergency order was made to manufacture quantities of ammunition that matched the ballistics of the older cartridge as soon as possible. A new cartridge was developed in 1938 that was essentially a duplicate of the old M1906 round, but with a gilding metal jacket and a different lead alloy, resulting in a bullet that weighed 152 grains (9.8 g) instead of 150. This cartridge, the Cartridge .30 M2 Ball, used a flat-based bullet fired at a higher muzzle velocity (2,805 ft/s) than either of its predecessors.
In military service, the 30-06 was used in the bolt-action M1903 Springfield rifle, the bolt-action M1917 Enfield rifle, the semi-automatic M1 Garand, the M1941 Johnson Rifle, the Famage Mauser, the Browning Automatic Rifle (BAR), and numerous machine guns, including the M1919 series. It served the United States in both World Wars and in the Korean War, its last major use being in Vietnam. Large volumes of surplus brass made it the basis for dozens of commercial and wildcat cartridges, as well as being extensively used for reloading. In 1908 the Model 1895 Winchester lever action rifle became the first commercially produced sporting rifle chambered in 30-06.
Ballistically, the 30-06 is one of the most versatile cartridges ever designed. With "hot" hand-loads and a rifle capable of handling them, the .30-06 is capable of performance rivaling many "magnum" cartridges. The .30-06's power (combined with the availability of surplus firearms chambered for it and demand for commercial ammunition) has kept the round as one of the most popular for hunting in North America. With appropriate loads it is suitable for any small or large heavy game found in North America.
The .30-06 cartridge was designed when shots of 1,000 yards (900 m) were expected. In 1906, the original M1906 .30-06 cartridge consisted of a 150 grains (9.7 g), flat-base cupronickel-jacketed-bullet. After WWI, the U.S. military needed better long-range performance machine guns. Based on weapons performance reports from Europe, a streamlined, 173 grains (11.2 g) boattail, gilding-metal bullet was used. The .30-06 cartridge, with the 173 grains (11.2 g) bullet was called Cartridge, .30, M1 Ball. The .30-06 cartridge was far more powerful than the smaller Japanese 6.5 x 50mm Arisaka cartridge and comparable to the Japanese 7.7 x 58 Arisaka. The new M1 ammunition proved to be significantly more accurate than the M1906 round.[5]
In 1938, the unstained, 9.8 grams (151 gr), flat-base bullet combined with the .30-06 case became the M2 ball cartridge. The M2 Ball specifications required 2,740 feet per second (840 m/s) minimum velocity, measured 78 feet (24 m) from the muzzle.[6] M2 Ball was the standard-issue ammunition for military rifles and machine guns until it was replaced by the 7.62 x 51 mm NATO round for the M14 and M60. For rifle use, M2 Ball ammunition proved to be less accurate than the earlier M1 cartridge; even with match rifles, a target group of 5 inches (130 mm) diameter at 200 yards (180 m) using the 150-grain (9.7 g) M2 bullet was considered optimal, and many rifles performed less well.[5] The U.S. Marine Corps retained stocks of M1 ammunition for use by snipers and trained marksmen throughout the Solomon Islands campaign in the early years of the war.[7] In an effort to increase accuracy some snipers resorted to use of the heavier .30-06 M2 armor-piercing round, a practice that would re-emerge during the Korean War.[8] Others sought out lots of M2 ammunition produced by Denver Ordnance, which had proved to be more accurate than those produced by other wartime ammunition plants when used for sniping at long range.[9] Commercially manufactured rifles chambered in .30-06 are popular for hunting.
Current .30-06 factory ammunition varies in bullet weight from 7.1 g to 14.3 g (110 to 220 grains) in solid bullets, and as low as 3.6 g (55 grains) with the use of a sub-caliber bullet in a sabot. Loads are available with reduced velocity and pressure as well as increased velocity and pressure for stronger firearms. The .30-06 remains one of the most popular sporting cartridges in the world. Many hunting loads have over 3,000 ft-lbs of energy at the muzzle and use expanding bullets that can deliver rapid energy transfer to living targets.
| Bullet Weight (grains) | Commercial[10] | Hodgdon[11] | Speer[12] | Hornady[13] | Nosler[14] | Barnes[15] |
|---|---|---|---|---|---|---|
| 110 | N/A | 3505 | 3356 | 3500 | N/A | 3471 |
| 125/130 | 3140 | 3334 | 3129 | 3200 | 3258 | 3278 |
| 150 | 2910 | 3068 | 2847 | 3100 | 3000 | 3031 |
| 165 | 2800 | 2938 | 2803 | 3015 | 3002 | 2980 |
| 180 | 2700 | 2798 | 2756 | 2900 | 2782 | 2799 |
| 200 | N/A | 2579 | 2554 | N/A | 2688 | 2680 |
| 220 | 2400 | 2476 | N/A | 2500 | 2602 | 2415 |
The table above shows typical muzzle velocities (in ft/s) available in commercial 30-06 loads along with maximum 30-06 muzzle velocities reported by several reloading manuals for common bullet weights. Hodgdon, Nosler, and Barnes report velocities for 24" barrels. Hornady and Speer report velocities for 22" barrels. The data are all for barrels with a twist rate of 1 turn in 10” which is needed to stabilize the heaviest bullets. The higher muzzle velocities reported by Nosler for 165 grain and heavier bullets use loads employing a slow-burning, double-base powder (Alliant Reloder 22).
The newer 7.62x51mm NATO/.308 Winchester cartridge offers similar performance to standard military .30-06 loadings in a smaller cartridge. However, the greater cartridge capacity of the .30-06 allows much more powerful loadings if the shooter desires.
One reason that the 30-06 has remained entrenched as an extremely popular round for so long is that the cartridge is at the upper limit of power that is tolerable to most shooters.[16] [17] Recoil energy (Free recoil) greater than 20 foot pounds (27.1 joules) will cause most shooters to develop a serious flinch, and the recoil energy of an 8 pound 30-06, firing a 165 grain bullet at 2900 ft/s is 20.1 foot pounds (27.3 joules). Recoil shy shooters can opt for lighter bullets, such as a 150 grain. In the same 8 pound rifle, a 150 grain bullet at 2910 ft/s will only generate 17.6 foot pounds (23.9 joules) of recoil energy.[18] Young shooters can start out with even lighter bullets such as the 110, 125 or 130
The .30-06 Springfield has a 68.2 grains (4.43 ml ) 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.
.30-06 Springfield maximum C.I.P. cartridge dimensions. All sizes in millimeters.
Americans defined the shoulder angle at alpha/2 = 17.5 degrees. According to the Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives (C.I.P.) the common rifling twist rate for this cartridge is 254 mm (1 in 10 in), 4 grooves, Ø lands = 7.62 mm (.30 in), Ø grooves = 7.82 mm (.308 in), land width = 4.49 mm (.1768 in) and the primer type is large rifle. According to the official C.I.P. guidelines, the .30-06 Springfield case can handle up to 405 Mpa (58,740 psi) piezo pressure. In C.I.P.-regulated countries, every rifle cartridge combination has to be proofed at 125% of this maximum C.I.P. pressure to certify for sale to consumers. The 8x64mm S is probably the closest European ballistic twin of the .30-06 Springfield.
Note: .30-06 cartridges are produced commercially with many different bullets and to a number of different specifications.
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