.30-06 Springfield

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.30-06 Springfield
30-06 Springfield rifle cartridge.jpg
.30-06 Springfield cartridge with soft tip
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 (4.4 cm3)
Rifling twist 1 turn in 10 inches (25.4 cm)
Primer type Large Rifle
Maximum pressure 60,200 psi (415 MPa)
Ballistic performance
Bullet weight/type Velocity Energy
150 gr (10 g) Nosler Ballistic Tip 2,910 ft/s (890 m/s) 2,820 ft·lbf (3,820 J)
165 gr (11 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]

The .30-06 Springfield cartridge (pronounced "thirty-aught-six" or "thirty-oh-six"), 7.62×63mm in metric notation and called "30 Gov't 06" by Winchester[3] was introduced to the United States Army in 1906 and later standardized; it remained in use until the early 1970s. The ".30" refers to the caliber of the bullet, and the "06" refers to the year the cartridge was adopted—1906. It replaced the .30-03, 6 mm Lee Navy, and .30-40 Krag cartridges. (The .30-40 Krag is also called the .30 U.S., .30 Army, or .30 Government.) The .30-06 remained the U.S. Army's primary rifle and machine gun cartridge for nearly 50 years before being replaced by the 7.62×51mm NATO (commercial .308 Winchester) and 5.56×45mm NATO, 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.

History[edit]

Many European militaries at the turn of the 20th century were in the process of adopting service rounds loaded with pointed spitzer bullets: France in 1898, Germany in 1905, Russia in 1908, and Britain in 1910,[4] so when it was introduced in 1903, the .30-03 service round loaded with a 220-grain (14 g) round-nose bullet and achieving a muzzle velocity of 2,300 ft/s (700 m/s) was quickly falling behind the ongoing technical evolution.[5]

For these reasons a new case was developed with a slightly shorter neck to fire a spitzer flat-based 150 grains (9.7 g) bullet that had a ballistic coefficient (G1 BC) of approximately 0.405 and achieved a muzzle velocity of 2,700 ft/s (820 m/s) and muzzle energy of 2,428 ft·lbf (3,292 J). The M1903 Springfield rifle, introduced alongside the earlier .30-03 cartridge, was quickly modified to accept the new .30-06 Springfield cartridge, designated by the US military as the M1906. Modifications to the rifle included shortening the barrel at its breech and resizing the chamber, 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.[6] For these reasons, in 1926, the Ordnance Corps developed the .30 M1 Ball cartridge loaded with a new Improved Military Rifle (IMR) propellant and 174-grain (11.3 g) bullet with a 9 degree boat tail that had a higher ballistic coefficient of roughly 0.494 G1,[7] that achieved a muzzle velocity of 2,640 ft/s (800 m/s) and muzzle energy of 2,692 ft·lbf (3,650 J). This bullet further reduced air resistance in flight resulting in less rapid downrange deceleration, less lateral drift caused by crosswinds, and significantly greater supersonic and maximum effective range from machine guns and rifles alike. Its maximum range was approximately 5,500 yd (5,030 m).[8] Additionally, a gilding metal jacket was developed that all but eliminated the metal fouling that plagued the earlier M1906 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 .30 M1 Ball ammunition were allowed to slowly grow until all of the older M1906 ammunition had been fired. By 1936 it was discovered that the maximum range of the .30 M1 Ball ammunition with its boat-tailed spitzer bullets were beyond the safety limitations of many ranges. An emergency order was made to manufacture quantities of ammunition that matched the external ballistics of the earlier M1906 cartridge as soon as possible. A new cartridge was developed in 1938 that was essentially a duplicate of the old M1906 round, but loaded with IMR 4895 propellant and a new flat-based bullet that had gilding metal jacket and a different lead alloy and weighed 152 grains (9.8 g) instead of 150 grains (9.7 g). This 1938 pattern cartridge, the Cartridge, Caliber .30, Ball, M2 achieved a muzzle velocity of 2,805 ft/s (855 m/s) and muzzle energy of 2,655 ft·lbf (3,600 J). Its maximum range was approximately 3,450 yd (3,150 m).[8]

Firearms[edit]

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 M1917 and 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.It is still a very common round for hunting and is suitable for large game such as bison, Sambar deer, and bear, when used at close to medium ranges.

Ballistically, the 30-06 is one of the most versatile cartridges ever designed. With "hot" handloads and a rifle capable of handling them, the .30-06 is capable of performance rivaling many "magnum" cartridges. On the other hand, when loaded more closely to the original government spec, .30-06 remains within the upper limit of felt recoil most shooters consider 'tolerable' over multiple rounds, unlike the magnums; and isn't unnecessarily destructive of meat on game such as deer. With appropriate loads it is suitable for any small or large heavy game found in North America. The .30-06's power and versatility (combined with the availability of surplus firearms chambered for it and demand for commercial ammunition) have kept the round as one of the most popular for hunting in North America.

Performance[edit]

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 6.5×50mm Arisaka cartridge and comparable to the Japanese 7.7×58mm Arisaka. The new M1 ammunition proved to be significantly more accurate than the M1906 round.[9]

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.[10] M2 Ball was the standard-issue ammunition for military rifles and machine guns until it was replaced by the 7.62×51 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.[9] 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.[11] 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.[12] 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.[13] Commercially manufactured rifles chambered in .30-06 are popular for hunting.

Winchester .30-06 cartridge
From left to right 9.3x62mm, .30-06 Springfield, 7.92×57mm Mauser, 6.5×55mm and .308 Winchester
Eight .30-06 cartridges loaded to an en bloc clip for the M1 Garand

Current .30-06 factory ammunition varies in bullet weight from 7.1 to 14.3 grams (109.6 to 220.7 gr) in solid bullets, and as low as 3.6 grams (55.6 gr) 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 foot-pounds (4,100 J) of energy at the muzzle and use expanding bullets that can deliver rapid energy transfer to targets.

Bullet Weight Federal[14] Hodgdon[15] Speer[16] Hornady[17] Nosler[18] Barnes[19]
110 gr (7.1 g) N/A 3,505 ft/s (1,068 m/s) 3,356 ft/s (1,023 m/s) 3,500 ft/s (1,100 m/s) N/A 3,471 ft/s (1,058 m/s)
125–130 gr (8.1–8.4 g) 3,140 ft/s (960 m/s) 3,334 ft/s (1,016 m/s) 3,129 ft/s (954 m/s) 3,200 ft/s (980 m/s) 3,258 ft/s (993 m/s) 3,278 ft/s (999 m/s)
150 gr (9.7 g) 2,910 ft/s (890 m/s) 3,068 ft/s (935 m/s) 2,847 ft/s (868 m/s) 3,100 ft/s (940 m/s) 3,000 ft/s (910 m/s) 3,031 ft/s (924 m/s)
165 gr (10.7 g) 2,800 ft/s (850 m/s) 2,938 ft/s (896 m/s) 2,803 ft/s (854 m/s) 3,015 ft/s (919 m/s) 3,002 ft/s (915 m/s) 2,980 ft/s (910 m/s)
180 gr (11.7 g) 2,700 ft/s (820 m/s) 2,798 ft/s (853 m/s) 2,756 ft/s (840 m/s) 2,900 ft/s (880 m/s) 2,782 ft/s (848 m/s) 2,799 ft/s (853 m/s)
200 gr (13.0 g) N/A 2,579 ft/s (786 m/s) 2,554 ft/s (778 m/s) N/A 2,688 ft/s (819 m/s) 2,680 ft/s (820 m/s)
220 gr (14.3 g) 2,400 ft/s (730 m/s) 2,476 ft/s (755 m/s) N/A 2,500 ft/s (760 m/s) 2,602 ft/s (793 m/s) 2,415 ft/s (736 m/s)

The table above shows typical muzzle velocities 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 inches (610 mm) barrels. Hornady and Speer report velocities for 22 inches (560 mm) barrels. The data are all for barrels with a twist rate of 1 turn in 10 inches (250 mm) which is needed to stabilize the heaviest bullets. The higher muzzle velocities reported by Nosler for 165 grains (10.7 g) and heavier bullets use loads employing a slow-burning, double-base powder (Alliant Reloder 22).

The newer 7.62×51mm 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.

Recoil[edit]

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.[20][21] Recoil energy (Free recoil) greater than 20 foot-pounds force (27 J) will cause most shooters to develop a serious flinch, and the recoil energy of an 8 pounds (3.6 kg) rifle firing a 165 grains (10.7 g) 30-06 bullet at 2,900 feet per second (880 m/s) is 20.1 foot-pounds force (27.3 J). Recoil shy shooters can opt for lighter bullets, such as a 150 grains (9.7 g) bullet. In the same 8 pounds (3.6 kg), a 150 grains (9.7 g) bullet at 2,910 feet per second (890 m/s) will only generate 17.6 foot-pounds force (23.9 J) of recoil energy.[22] Young shooters can start out with even lighter bullets such as the 110, 125 or 130 grains (7.1, 8.1 or 8.4 g).

Cartridge dimensions[edit]

.30-06 Springfield cartridge dimensions. All sizes in inches

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.svg

.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.

U.S. military cartridge types[edit]

Note: .30-06 cartridges are produced commercially with many different bullets and to a number of different specifications.

  • Armor Piercing, M2 : This cartridge is used against lightly armored vehicles, protective shelters, and personnel, and can be identified by its black bullet tip. Bullet is flat base, weight 163-168 grains. Defense against the M2 projectile by name is one of the performance standards for Type IV body armor.[23]
  • Armor Piercing Incendiary, T15/M14 and M14A1: This cartridge may be substituted for the M2 armor piercing round and is normally employed against flammable targets. The tip of the bullet is colored with aluminum paint. The M14A1 featured an improved core design and incendiary charge.
  • Ball, M1906 : This cartridge is used against personnel and unarmored targets, and can be identified by its silver-colored bullet. The M1906 has a 9.7 g (150 grain) projectile and flat base. Its jacket is a cupro-nickel alloy which was found to quickly foul the bore.
  • Ball, M1: The M1 has a 11.2 g (173 grain), nine-degree boat-tailed projectile designed for aerodynamic efficiency. Though it had a lower initial velocity, velocity and energy were greater at longer ranges due to its efficient shape. The jacket material was changed to gilding metal to reduce fouling.
  • Ball, M2: With a 9.8 g (152 grain) bullet based on the profile of the M1906, this cartridge incorporated the gilding-metal jacket of the M1 projectile combined with a slightly heavier, pure-lead core. It had a higher muzzle velocity than either of the earlier cartridges.
  • Blank, M1909: This cartridge is used to simulate rifle fire. The cartridge is identified by having no bullet, and by a cannelure in the neck of the case which is sealed by red lacquer. This is still a current cartridge for ceremonial M1 Garands. Modern M1909 are rose crimped blanks, but they have the same designation.[24]
  • Dummy, M40: This cartridge is used for training. The cartridge has six longitudinal corrugations and there is no primer.
  • Explosive, T99: Development of a cartridge that contained a small explosive charge which more effectively marked its impact. Often referred to as an "observation explosive" cartridge, the T99 was never adopted.
  • Frangible, M22: The bullet disintegrates upon striking a hard or armored target, leaving a pencil-like mark to indicate a hit during gunnery practice. The cartridge is identified by a green bullet tip with a white ring to the rear of the green color.
  • High Pressure Test, M1: The cartridge is used to proof test 30-06 rifles and machine guns after manufacture, test, or repair. The cartridge is identified by stannic-stained (silvered) cartridge case.
  • Incendiary, M1917: Early incendiary cartridge, bullet had a large cavity in the nose to allow the material to more easily shoot forward on impact. As a result the M1917 had a tendency to expand on impact. The M1917 had a blackened tip.
  • Incendiary, M1918: Variant of the M1917 with a normal bullet profile to comply with international laws regarding open-tipped expanding bullets.
  • Incendiary, M1 : This cartridge is used against unarmored, flammable targets. The tip of the bullet is painted blue.
  • Match, M72: This cartridge is used in marksmanship competition firing, and can be identified by the word "MATCH" on the head stamp.
  • Tracer, M1: Tracer for observing fire, signaling, target designation, and incendiary purposes. The M1 has a red tip.
  • Tracer, M2: Tracer for observing fire, signaling, target designation, and incendiary purposes. Has a short burn time. The M2 originally had a white tip, but then switched to a red tip like the M1.
  • Tracer, T10/M25: Improved tracer over M1/M2. Designed to be less intense in terms of brightness than either the M1 or M2 tracers. The M25 had an orange tip.
  • Rifle Grenade Cartridges, M1, M2, and M3/E1: These cartridges are used in conjunction with the M1 (for the M1903 rifle), M2 (for the M1917 rifle), and the M7 series (for the M1 rifle) grenade launchers to propel rifle grenades. The cartridge has no bullet and the mouth is crimped. The differences between the three cartridges have to do with the powder charge and the subsequent range of the launched grenade. The M3E1 featured an extended case neck.[25][26] The Grenade Blanks were issued in double-rowed 10-round cartons, usually as part of a set with the M13 metal Grenade Launcher Assortment ammo can.[27]

U.S. military firearms using the .30-06 cartridge[edit]

View from the turret of an M67 "Zippo". On the right is a mounted M1919 Browning machine gun with an attached box of linked .30-06 ammunition.

See also[edit]

References[edit]

Notes
  1. ^ "Federal Cartridge Co. ballistics page". Archived from the original on 22 September 2007. Retrieved 2007-09-21. 
  2. ^ "Accurate Powder reload data table" (PDF). Archived from the original on 20 March 2009. Retrieved 2009-02-09. 
  3. ^ Gun Digest Shooter's Guide to Rifles, Wayne van Zwoll, p 186
  4. ^ http://www.303british.com/id19.html
  5. ^ The .30-06 Springfield Cartridge
  6. ^ George, John (Lt. Col.), Shots Fired In Anger, NRA Press (1981), pp. 402-403
  7. ^ https://www.snipercentral.com/m118.phtml
  8. ^ a b FM 23-10 Basic Field Manual: U.S. Rifle Caliber .30, M1903, 20 September 1943 page 212
  9. ^ a b Dunlap, Roy, Ordnance Went Up Front, Samworth Press (1948), p. 303 ISBN 978-1-884849-09-1
  10. ^ U.S. Army (April 1994), Army Ammunition Data Sheets: Small Caliber Ammunition, Technical Manual, TM 43-0001-27 , page 5-9
  11. ^ George, John (Lt. Col.), Shots Fired In Anger, NRA Press (1981), p. 409
  12. ^ Rocketto, Hap, Biography: William S. Brophy, Civilian Marksmanship Program http://clubs.odcmp.com/cgi-bin/distinguishedStory.cgi?distID=6674
  13. ^ George, John (Lt. Col.), Shots Fired In Anger, NRA Press (1981), pp. 81, 428, 434-435
  14. ^ http://www.federalpremium.com/products/rifle.aspx accessed 15 May 2010
  15. ^ Hodgdon Powder Company, Cartridge Load Recipe Report, 3/27/2010, data.hodgdon.com
  16. ^ Speer Reloading Manual Number 12, 1994, Blount, Inc., Lewiston, ID. pp. 286-294.
  17. ^ Hornady Handbook of Cartridge Reloading, Fourth Edition, 1991, Hornady Manufacturing Company, Grand Island, NE. pp. 343-350.
  18. ^ Nosler Reloading Guide Number Four, 1996, Nosler, Inc., Bend OR. pp. 322-329.
  19. ^ Barnes Reloading Manual Number 2-Rifle Data, 1997, Barnes Bullets, Inc., American Fork, UT. pp. 381-386.
  20. ^ Barnes, Frank C., Cartridges of the World (Kindle Edition), 2009, Frank C. Barnes and Krause Publications, Chapter 2, Location 375
  21. ^ http://www.gunnersden.com/index.htm.30-06springfield.html
  22. ^ http://www.chuckhawks.com/recoil_table.htm
  23. ^ "Ballistic Resistance of Body Armor NIJ Standard-0101.06" (PDF). NIJ Standards. United States Department of Justice. July 2008. Retrieved 2008-11-13. 
  24. ^ Use of M1909 blanks in M1 rifles.
  25. ^ "Gary's U.S. Infantry Weapons Reference Guide - .30 Caliber (.30-06 Springfield) Ammunition". Archived from the original on 27 September 2007. Retrieved 2007-09-21. 
  26. ^ "An Introduction to Collecting .30-06". Archived from the original on 19 September 2007. Retrieved 2007-09-21. 
  27. ^ US Grenade Cartridges by Bill Riccia copyright March 2004
Bibliography