.338 Winchester Magnum
Encyclopedia
The .338 Winchester Magnum is a .33 caliber (8.38 mm) belted rimless bottlenecked cartridge introduced in 1958 by Winchester Repeating Arms Company|Winchester. It is based on the blown out, shortened .375 H&H Magnum. The .33 (8.38mm) is the caliber at which medium bore cartridges are considered to begin. Hence, the .338 Winchester Magnum is considered a first option for those requiring a medium bore cartridge. It is the most popular medium bore cartridge in North America and one of the most popular magnum cartridges currently available. The cartridge was intended for larger North American big game species and has found use as for the hunting of thin-skinned African plains game species.
The .338 Winchester Magnum was introduced in 1958 together with the .264 Winchester Magnum
and the .458 Winchester magnum
; all of which used a common case design based on the .375 H&H Magnum case blown out and shortened to 2.5 in (63.5 mm) much like the .334 OKH. When the cartridge was introduced, Winchester offered a 200 gr at 3000 ft/s (914.4 m/s), a 250 gr at 2700 ft/s (823 m/s) and a 300 gr at 2450 ft/s (746.8 m/s). Sometime later, Winchester introduced the Winchester Model 70 Alaskan chambered for the cartridge. This chambering left little doubt that the cartridge was intended for big heavy dangerous game.
, .270 Weatherby Magnum
and the 7 mm Weatherby Magnum
for which Winchester had supplied basic brass until 1948.
Both the Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives
(CIP) and the Sporting Arms and Ammunition Manufacturers' Institute
(SAAMI) govern and regulate the specifications regarding the .338 Winchester Magnum.
SAAMI and the CIP recommend a 6 groove barrel with a twist rate of one revolution in 10 in (254 mm) barrel with a bore Ø of 0.33 in (8.4 mm) and a grove diameter of Ø of 0.33 in (8.4 mm) with each groove having a width of 0.11 in (2.8 mm). The SAAMI recommended average peak pressure for the cartridge is 65000 psi (4,481.6 bar). The CIP enforces a 4300 bar (62,366.2 psi) pressure limit for the cartridge.
(14.58g) bullet
to velocities
of 2,800 ft/s (853.44 m/s), generating 3,918 ft·lbf (5258 J), providing energy values at 200 yards that are roughly equivalent to the .30-06 Springfield
's energy values at muzzle
. Bullets are available in a very wide range of designs and weights ranging from 160 to 300 grains. SAAMI
pressure level is 64,000 p.s.i.
The .338 Winchester Magnum is capable of launching heavier bullets than the .30 caliber (7.62mm) cartridges. The most common bullets loaded for the .338 Winchester range from 200 gr to 250 gr. Typical bullet weights for factory ammunition are , , and the . Typical velocities for these bullet weights range from 2960 ft/s (902.2 m/s) for the to about 2660 ft/s (810.8 m/s) for the bullet each generating approximately 3900 ft·lbf (5,287.7 J) of energy. This is approximately 25% more energy generated than the 30-06 Springfield.
Winchester’s Ballistic Silvertip ammunition (SBST338) retains over 1600 ft·lbf (2,169.3 J) at 625 yd (571.5 m) and has 1000 ft·lbf (1,355.8 J) energy at 800 yd (731.5 m). Winchester’s Combined Technologies Accubond ammunition (S338CT) extend the range for these energy levels even further to 675 yd (617.2 m) and 850 yd (777.2 m) respectively.
The recoil
of this caliber
is quite heavy, with about 31 ft·lbf (4.16 m*kg) of recoil energy in a 9 lb (4.08 kg) rifle. This is about twice as much as the recoil from an average .308 Winchester
. Strong recoil like this can be mitigated with the use of properly designed stocks and recoil pads. By comparison, this cartridge has less recoil than other more powerful .338-caliber rifles such as the .338 RUM
, .340 Weatherby
and .338 Lapua
.
Use of a muzzle brake such as the highly efficient JP Howitzer brake can reduce or virtually eliminate recoil from these rifles. Use of brakes will, however, increase greatly the blast noise through the diversion of muzzle gases to the sides.
In North America, the .338 Winchester Magnum is most commonly used for the hunting of larger deer species such as elk and moose. Due to its popularity with elk hunters and its effectiveness as an elk cartridge it is known as the “King of the Elk Cartridges”. Bullets ranging between 200 gr are generally preferred for the hunting of elk and even moose.
Apart from the larger deer species, the .338 Winchester Magnum is often used for the hunting of and defense against the great bears such as the grizzly, polar and brown bears. It is often carried by fishermen, hunters and guides in Alaska and Canada for protection as encounters with these larger bear species can be common.
The .338 Winchester Magnum can be considered a good all-round plains game hunting rifle in Africa. It has also been found to be effective against the big cats where hunting allows for the use of the cartridge.
, Kimber
, Remington
, Savage
, Weatherby
, Howa
and Winchester
chamber the cartridge in several product lines. Almost all custom rifle makers in the United States and Canada produce .338 Winchester rifles. In European rifle makers Blaser
, Mauser
, Sako
and Tikka
also manufacture rifles for this cartridge. The large number of rifle choices available in the .338 Winchester Magnum offers the rifleman a greater choice in available rifle platforms.
All North American ammunition makers offer several loadings of the .338 Winchester Magnum to the public for sale. At this point in time Federal has six in their Vital-Shok and Fusion ammunition lines, Hornady has five, including four in their Superformance ammunition which is putting an end to the light magnum and heavy magnum line of ammo but adds up to 200 ft/s (61 m/s) more without added recoil or muzzle blast. The 185 gr. GMX (gliding metal expanding) round has the following performance: 3080 ft/s (938.8 m/s) at the muzzle, 2850 ft/s (868.7 m/s) at 100 yards, 3,896 ft⋅lbf (5,282 J) of kinetic energy
at the muzzle and 3,337 ft⋅lbf (4,524 J) at 100 yards. 200 gr. SST, 225 gr. interbond, 225 gr. SST are all excellent big game rounds, and the 185 gr. is a wonderful deer round. Remington and Winchester offer four loadings each for the cartridge. Several smaller ammunition including Cor-Bon and Double Tap also manufacture loaded ammunition.
Cartridge history
The .338 Winchester Magnum traces its heritage to the experiments conducted by Charles O’Neil, Elmer Keith and Don Hopkins with cartridges firing 0.333 in (8.5 mm) bullets in the late 1940s. The use of 0.333 in (8.5 mm) bullets may seem odd today but at the time this was the standard diameter of European .33 caliber bullets which were more common than the 0.338 in (8.6 mm) diameter bullets used in cartridges such as the .33 Winchester. Furthermore the 0.333 in (8.5 mm) were available in heavier weights than the 0.338 in (8.6 mm) bullets. O’Neil, Keith and Hopkins experiments lead to the creation of the .333 OKH, which was based on the .30-06 Springfield case necked up to accept .33 caliber bullets and the .334 OKH which used a shortened .375 H&H Magnum necked down to accept the same bullets.The .338 Winchester Magnum was introduced in 1958 together with the .264 Winchester Magnum
.264 Winchester Magnum
The .264 Winchester Magnum is a belted, bottlenecked rifle cartridge. Apart from the .257 Weatherby Magnum, it is the smallest caliber factory cartridge which uses the standard length Holland & Holland belted magnum case...
and the .458 Winchester magnum
.458 Winchester Magnum
The .458 Winchester Magnum is a belted, straight-taper cased, dangerous game rifle cartridge. It was introduced commercially in 1956 by Winchester and first chambered in the Winchester Model 70 African rifle. It was designed to compete against the .450 Nitro Express and the .470 Nitro Express...
; all of which used a common case design based on the .375 H&H Magnum case blown out and shortened to 2.5 in (63.5 mm) much like the .334 OKH. When the cartridge was introduced, Winchester offered a 200 gr at 3000 ft/s (914.4 m/s), a 250 gr at 2700 ft/s (823 m/s) and a 300 gr at 2450 ft/s (746.8 m/s). Sometime later, Winchester introduced the Winchester Model 70 Alaskan chambered for the cartridge. This chambering left little doubt that the cartridge was intended for big heavy dangerous game.
Design and specifications
The .338 winchester Magnum follows the modern cartridge designs in that the cartridge case features a case with minimal taper so as to maximize case capacity yet providing reliable feeding and extraction. The .338 Winchester Magnum is based on the .375 H&H Magnum, which was shortened to 2.5 in (63.5 mm), blown out and necked down to hold a 0.338 in (8.6 mm) bullet. The case has a capacity of 86.0 grain of H2O (5.58 cm3). The cartridge follows the design of the standard length Weatherby Magnum cartridges such as the .257 Weatherby Magnum.257 Weatherby Magnum
The .257 Weatherby Magnum is a .25 Caliber belted bottlenecked cartridge. It is one of the original standard length magnums developed by shortening the .375 H&H Magnum case to approx....
, .270 Weatherby Magnum
.270 Weatherby Magnum
The .270 Weatherby Magnum was the first belted magnum based on the .300 H&H Magnum to be developed by Roy Weatherby. It has the characteristic double-radius shoulders and is necked down to accommodate the .277in bullets. Being a proprietary cartridge, the .270 Weatherby has no official SAAMI...
and the 7 mm Weatherby Magnum
7 mm Weatherby Magnum
The 7 mm Weatherby Magnum is a powerful 7 mm rifle cartridge offered by the Weatherby firearms company in their Mark V rifles. The cartridge was one of the first cartridges offered by the Weatherby company....
for which Winchester had supplied basic brass until 1948.
Both the Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives
Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives
The Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives is an international organisation whose members are 14 states, mainly European....
(CIP) and the Sporting Arms and Ammunition Manufacturers' Institute
Sporting Arms and Ammunition Manufacturers' Institute
The Sporting Arms and Ammunition Manufacturers' Institute is an association of American firearms and ammunition manufacturers...
(SAAMI) govern and regulate the specifications regarding the .338 Winchester Magnum.
SAAMI and the CIP recommend a 6 groove barrel with a twist rate of one revolution in 10 in (254 mm) barrel with a bore Ø of 0.33 in (8.4 mm) and a grove diameter of Ø of 0.33 in (8.4 mm) with each groove having a width of 0.11 in (2.8 mm). The SAAMI recommended average peak pressure for the cartridge is 65000 psi (4,481.6 bar). The CIP enforces a 4300 bar (62,366.2 psi) pressure limit for the cartridge.
Performance
This cartridge is able to push a 225 grainGrain (measure)
A grain is a unit of measurement of mass that is nominally based upon the mass of a single seed of a cereal. From the Bronze Age into the Renaissance the average masses of wheat and barley grains were part of the legal definition of units of mass. However, there is no evidence of any country ever...
(14.58g) bullet
Bullet
A bullet is a projectile propelled by a firearm, sling, or air gun. Bullets do not normally contain explosives, but damage the intended target by impact and penetration...
to velocities
Velocity
In physics, velocity is speed in a given direction. Speed describes only how fast an object is moving, whereas velocity gives both the speed and direction of the object's motion. To have a constant velocity, an object must have a constant speed and motion in a constant direction. Constant ...
of 2,800 ft/s (853.44 m/s), generating 3,918 ft·lbf (5258 J), providing energy values at 200 yards that are roughly equivalent to the .30-06 Springfield
.30-06 Springfield
The .30-06 Springfield cartridge 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...
's energy values at muzzle
Muzzle (firearm)
The muzzle of a firearm is the end of the barrel from which the projectile will exit.Precise machining of the muzzle is crucial to accuracy, because it is the last point of contact between the barrel and the projectile...
. Bullets are available in a very wide range of designs and weights ranging from 160 to 300 grains. SAAMI
Saami
Saami or SAAMI can stand for:*Sami people*Sami languages*Sporting Arms and Ammunition Manufacturers' Institute...
pressure level is 64,000 p.s.i.
Pounds per square inch
The pound per square inch or, more accurately, pound-force per square inch is a unit of pressure or of stress based on avoirdupois units...
The .338 Winchester Magnum is capable of launching heavier bullets than the .30 caliber (7.62mm) cartridges. The most common bullets loaded for the .338 Winchester range from 200 gr to 250 gr. Typical bullet weights for factory ammunition are , , and the . Typical velocities for these bullet weights range from 2960 ft/s (902.2 m/s) for the to about 2660 ft/s (810.8 m/s) for the bullet each generating approximately 3900 ft·lbf (5,287.7 J) of energy. This is approximately 25% more energy generated than the 30-06 Springfield.
Winchester’s Ballistic Silvertip ammunition (SBST338) retains over 1600 ft·lbf (2,169.3 J) at 625 yd (571.5 m) and has 1000 ft·lbf (1,355.8 J) energy at 800 yd (731.5 m). Winchester’s Combined Technologies Accubond ammunition (S338CT) extend the range for these energy levels even further to 675 yd (617.2 m) and 850 yd (777.2 m) respectively.
The recoil
Recoil
Recoil is the backward momentum of a gun when it is discharged. In technical terms, the recoil caused by the gun exactly balances the forward momentum of the projectile and exhaust gasses, according to Newton's third law...
of this caliber
Caliber
In guns including firearms, caliber or calibre is the approximate internal diameter of the barrel in relation to the diameter of the projectile used in it....
is quite heavy, with about 31 ft·lbf (4.16 m*kg) of recoil energy in a 9 lb (4.08 kg) rifle. This is about twice as much as the recoil from an average .308 Winchester
.308 Winchester
The .308 Winchester is a rifle cartridge and is the commercial cartridge upon which the military 7.62x51mm NATO centerfire cartridge is based. The .308 Winchester was introduced in 1952, two years prior to the NATO adoption of the 7.62x51mm NATO T65...
. Strong recoil like this can be mitigated with the use of properly designed stocks and recoil pads. By comparison, this cartridge has less recoil than other more powerful .338-caliber rifles such as the .338 RUM
.338 Remington Ultra Magnum
The .338 Remington Ultra Magnum is a .338 caliber rifle cartridge introduced by Remington Arms in 2002. It is a beltless, rebated rim cartridge based on the .300 Remington Ultra Magnum case shortened .090" loaded with a .338 caliber bullet...
, .340 Weatherby
.340 Weatherby Magnum
The .340 Weatherby Magnum rifle cartridge was introduced in 1963 by creator Roy Weatherby in response to the .338 Winchester Magnum. The .340 Weatherby Magnum uses the same .338 in. diameter bullets as the .338 Winchester Magnum but it does so at greater velocity than its Winchester competition...
and .338 Lapua
.338 Lapua
The .338 Lapua Magnum is a specialized rimless bottlenecked centerfire cartridge developed for military long-range sniper rifles. The Afghanistan War and Iraq War made it a combat-proven round with ready and substantial ammunition availability...
.
Use of a muzzle brake such as the highly efficient JP Howitzer brake can reduce or virtually eliminate recoil from these rifles. Use of brakes will, however, increase greatly the blast noise through the diversion of muzzle gases to the sides.
Sporting usage
When the .338 Winchester was introduced there was a general preference for heavier bullet weights between 250 gr. However, since that time preferred bullet weights have decreased to weights between 200 gr. This is due in part to the bullet technology available today. Lighter bullets made today are able to hold together and penetrate deeper than heavier bullets of the past.In North America, the .338 Winchester Magnum is most commonly used for the hunting of larger deer species such as elk and moose. Due to its popularity with elk hunters and its effectiveness as an elk cartridge it is known as the “King of the Elk Cartridges”. Bullets ranging between 200 gr are generally preferred for the hunting of elk and even moose.
Apart from the larger deer species, the .338 Winchester Magnum is often used for the hunting of and defense against the great bears such as the grizzly, polar and brown bears. It is often carried by fishermen, hunters and guides in Alaska and Canada for protection as encounters with these larger bear species can be common.
The .338 Winchester Magnum can be considered a good all-round plains game hunting rifle in Africa. It has also been found to be effective against the big cats where hunting allows for the use of the cartridge.
Rifles and ammunition
Due to the cartridge’s popularity all North American rifle manufacturers offer rifles chambered in the .338 Winchester Magnum. Ruger, BrowningBrowning
-Places:* Browning, Illinois, USA* Browning, Montana, USA* Browning, Wisconsin, USA* Browning, Missouri, USA* Browning Hill, in Brown County, Indiana; sometimes called Browning Mountain* Browning, Saskatchewan, Canada* Browning No...
, Kimber
Kimber
-People:* Kimber * Kimber may also refer to the Germanic tribe of the Cimbri.-Companies:*Kimber Manufacturing, a firearms company that produces a wide variety of weapons, notably their M1911 pistols.*Project Kimber-Firearms:...
, Remington
Remington
- People :* Eliphalet Remington , American firearms designer* Philo Remington , American firearms and typewriter manufacturer, son of Eliphalet Remington* Frederic Remington , American painter and sculptor...
, Savage
Savage
- Places :Canada* Lower Savage Islands, Nunavut* Middle Savage Islands, NunavutSlovenia* Savage Lake, a karst lakeUnited States* Savage, Maryland* Savage, Minnesota...
, Weatherby
Weatherby
Weatherby, Inc. is an American gun manufacturer founded in 1945 by Roy Weatherby. The company is best known for its high-powered magnum cartridges, such as the .257 Weatherby Magnum and the .460 Weatherby Magnum...
, Howa
Howa
) is a Japanese machinery manufacturer. The company is known internationally for their production of military and civilian firearms. However, they also manufacture civilian products such as industrial tools, construction vehicles and windows and doors....
and Winchester
Winchester
Winchester is a historic cathedral city and former capital city of England. It is the county town of Hampshire, in South East England. The city lies at the heart of the wider City of Winchester, a local government district, and is located at the western end of the South Downs, along the course of...
chamber the cartridge in several product lines. Almost all custom rifle makers in the United States and Canada produce .338 Winchester rifles. In European rifle makers Blaser
Blaser
Blaser Jagdwaffen GmbH is a firearms manufacturer mostly of hunting rifles in Germany.It was founded in 1957 by Horst Blaser, developing the Drilling Blaser Diplomat....
, Mauser
Mauser
Mauser was a German arms manufacturer of a line of bolt-action rifles and pistols from the 1870s to 1995. Mauser designs were built for the German armed forces...
, Sako
SAKO
SAKO, Limited is a Finnish firearm manufacturer located in Riihimäki....
and Tikka
Tikka
Tikka may refer to:* Tikka , a type of Indian food * Tikka , a mark made on the forehead by Hindu Indians...
also manufacture rifles for this cartridge. The large number of rifle choices available in the .338 Winchester Magnum offers the rifleman a greater choice in available rifle platforms.
All North American ammunition makers offer several loadings of the .338 Winchester Magnum to the public for sale. At this point in time Federal has six in their Vital-Shok and Fusion ammunition lines, Hornady has five, including four in their Superformance ammunition which is putting an end to the light magnum and heavy magnum line of ammo but adds up to 200 ft/s (61 m/s) more without added recoil or muzzle blast. The 185 gr. GMX (gliding metal expanding) round has the following performance: 3080 ft/s (938.8 m/s) at the muzzle, 2850 ft/s (868.7 m/s) at 100 yards, 3,896 ft⋅lbf (5,282 J) of kinetic energy
Kinetic energy
The kinetic energy of an object is the energy which it possesses due to its motion.It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes...
at the muzzle and 3,337 ft⋅lbf (4,524 J) at 100 yards. 200 gr. SST, 225 gr. interbond, 225 gr. SST are all excellent big game rounds, and the 185 gr. is a wonderful deer round. Remington and Winchester offer four loadings each for the cartridge. Several smaller ammunition including Cor-Bon and Double Tap also manufacture loaded ammunition.