The .300 Winchester Magnum
(known as .300 Win Mag
) is a popular, belted
The term belted magnum refers to any caliber cartridge, generally rifles, using a shell casing with a pronounced "belt" around its base that continues 2-4mm past the extractor groove. This design originated with the British gunmaker Holland & Holland for the purpose of headspacing certain of...
, bottlenecked magnum rifle
A rifle is a firearm designed to be fired from the shoulder, with a barrel that has a helical groove or pattern of grooves cut into the barrel walls. The raised areas of the rifling are called "lands," which make contact with the projectile , imparting spin around an axis corresponding to the...
A cartridge, also called a round, packages the bullet, gunpowder and primer into a single metallic case precisely made to fit the firing chamber of a firearm. The primer is a small charge of impact-sensitive chemical that may be located at the center of the case head or at its rim . Electrically...
that was introduced by Winchester Repeating Arms Company in 1963 as a member of the family of Winchester Magnum
Winchester Magnum refers to a "family" of cartridges developed by the Winchester Repeating Arms Company , one of the oldest firearms manufacturers in the United States, in the late 1950s and early 1960s, all based on the same basic cartridge case...
cartridges. The .300 Winchester Magnum is a magnum cartridge designed to fit in a standard length action. It is based on the .375 H&H Magnum, which has been blown out, shortened, and necked down to accept a .30 caliber (7.62 mm) bullet.
The .300 Winchester is extremely versatile and has been adopted by many shooting disciplines. The cartridge has found use by hunters, target shooters, military units, and law enforcement departments. Hunters found that the cartridge was an effective all round hunting cartridge. The .300 Win Mag remains the most popular .30 caliber magnum with American hunters, despite being surpassed in performance by the more powerful .300 Weatherby Magnum
The .300 Weatherby Magnum is a .30 caliber rifle cartridge created by Roy Weatherby in 1944 and produced by Weatherby. It has become the most popular of all the Weatherby cartridges.-Background:...
and the newer .300 Remington Ultra Magnum. It is a popular selection for hunting moose
The moose or Eurasian elk is the largest extant species in the deer family. Moose are distinguished by the palmate antlers of the males; other members of the family have antlers with a dendritic configuration...
The Elk is the large deer, also called Cervus canadensis or wapiti, of North America and eastern Asia.Elk may also refer to:Other antlered mammals:...
, and bighorn sheep as it can deliver better long range performance with better bullet weight than most other .30 caliber (7.62mm) cartridges. Military and law enforcement
In North American English, a law enforcement agency is a government agency responsible for the enforcement of the laws.Outside North America, such organizations are called police services. In North America, some of these services are called police while others have other names In North American...
departments adopted the cartridge for long range sniping and marksmanship. As a testament to its accuracy, since its introduction it has gone on to win several 1000 yards (914.4 m) competitions.
Prior to the design of the .300 Winchester Magnum there were several cartridges which provided what could be best described as a magnum level of power. The heritage of .30 caliber (7.62 mm) magnums can be traced back to the .30 Newton in 1913 and to the .300 H&H Magnum
The .300 H&H Magnum Cartridge was introduced by the British company Holland & Holland as the Super-Thirty in June, 1925. The case was belted like the .375 H&H Magnum, and is based on the same case, as also is the .244 H&H Magnum. The belt is for headspace as the cases' shoulders have a narrow...
in 1925. Beginning with the .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...
in 1943, Roy Weatherby
Roy E. Weatherby was the founder and owner of Weatherby, Inc., an American rifle, shotgun and cartridge manufacturing company set up in 1945. Weatherby created an entire line of custom cartridges, and was one of the people responsible for the industry interest in high-speed cartridges...
introduced a line of cartridges based on a standard length (2.5 in (63.5 mm)) magnum case. This was accomplished by taking the .30 Super Belted Rimless H&H case and having it blown out (reducing the taper) and shortened so that it could be cycled through a standard length bolt action rifle. Then in 1944 he designed the .300 Weatherby Magnum which essentially was an improved version of the .30 Super Belted Rimless H&H, a close variant of the .300 H&H Magnum.
The Weatherby’s standard length magnum case was soon noticed. In 1958 Winchester introduced three cartridges - the .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...
, .338 Winchester Magnum and the .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 based on the shortened and blown out .375 H&H Magnum case. The popular .30 caliber’s omission from that lineup was not missed. Wildcatters soon produced the .30-338 Winchester and Norma Projektilfabrik, who were by now manufacturing ammunition for Weatherby, took the standard length basic Weatherby brass and necked it down to .30 caliber (7.62 mm) and called it the .308 Norma Magnum
The .308 Norma Magnum cartridge was created by Nils Kvale at Norma, Sweden. Like the larger .358 Norma Magnum it is based on the .300 H&H Magnum. The length of the case is the longest that would fit in a standard Mauser action. While it appeared to have a bright future initially, it was soon...
The .300 Winchester Magnum was introduced in 1963 by Winchester for use in the Model 70
The Winchester Model 70 is a bolt action sporting rifle. It has an iconic place in American sporting culture and has been held in high regard by shooters since it was introduced in 1936, earning the moniker "The Rifleman's Rifle". The action has some design similarities to Mauser designs and it is...
rifle. The introduction of the .300 Winchester Magnum was not unforeseen; rather, its introduction was anticlimactic. Winchester developed the .300 Winchester Magnum by taking the .338 Winchester Magnum which was introduced in 1958 and moved the shoulder forward by 0.156 inch (0.39624 cm) and lengthening it by 0.12 inch (0.3048 cm). This caused the cartridge to have a neck shorter than the diameter of the bullet. There has been some speculation that if the cartridge was released to the earlier, the dimensions of the cartridge would have matched the .30-338 Winchester wildcat cartridge. Since its introduction the cartridge has remained extremely popular.
The .300 Winchester Magnum's high availability in popular rifles such as Winchester's Model 70 and Remington Model 700
The Model 700 series of firearms are bolt-action rifles manufactured by Remington Arms since 1962. All are based on the same centerfire bolt action. They often come with a 3, 4 or 5-round internal magazine depending on caliber, some of which have a floor-plate for quick-unloading, and some of which...
made the cartridge a popular choice among the shooting public. Although the .300 H&H Magnum, .30-338 Winchester Magnum and the .308 Norma Magnum had a head start on the .300 Winchester Magnum these cartridges soon faded into obsolescence. Only the .300 Weatherby Magnum was to survive as a readily available cartridge.
Design & Specifications
The .300 Winchester uses the same case head design of the .375 H&H Magnum, its parent cartridge. The taper of the cartridge was reduced to provide the cartridge with more volume so as to increase its potential powder capacity. The lengthening of the case and the move of the shoulder forward over the .338 Winchester Magnum allowed for the reaming of the .308 Norma Magnum or .30-338 Winchester chamber to dimensions of the .300 Winchester Magnum. The down side was a neck which was shorter than the caliber of the bullet it fired which meant that the bullet had to be seated more deeply in the case.
Both SAAMI and CIP have provided specifications for the .300 Winchester Magnum cartridge. No divergence between CIP and SAAMI dimensional values exist for this cartridge. SAAMI recommends a bore diameter of 0.3 inches (7.6 mm) and a grove diameter of 0.308 inches (7.8 mm). SAAMI recommended a 6 groove barrel with each groove being 0.11 inches (2.8 mm) wide. Recommended twist ratio is 1:10.
While case volume will vary from manufacturer to manufacturer the typical Winchester case capacity of 93.8 grains of H2
O (6.08 cm3
). The maximum pressure of the cartridge given by CIP is 4300 bar (62,366.2 psi) and SAAMI recommended maximum pressure is 64000 psi (4,412.6 bar).
The Winchester’s factory ammunition for the .300 Winchester Magnum is capable of 3260 feet per second (993.6 m/s) with the 150 gr bullet and 3000 ft/s (914.4 m/s) with the 180 gr bullet. The maximum point blank range for the 150 gr bullet is 318 yards (290.8 m) yards when zeroed at 270 yards (246.9 m). The maximum point blank range for the 180 gr bullet is 300 yards when zeroed at 254 yards (232.3 m). The ability to zero the .300 Winchester Magnum and shoot without hold over to 300 yards (274.3 m) makes the cartridge one of the flatter shooting cartridges.
|| 100 yards (91.4 m)
|| 200 yards (182.9 m)
|| 300 yards (274.3 m)
|| 400 yards (365.8 m)
|| 500 yards (457.2 m)
| .308 Winchester (Winchester - SXP308) 150 gr
|| 2825 ft/s (861.1 m/s)
|| 2616 ft/s (797.4 m/s)
|| 2417 ft/s (736.7 m/s)
|| 2226 ft/s (678.5 m/s)
|| 2044 ft/s (623 m/s)
|| 1871 ft/s (570.3 m/s)
|| 2658 ft·lbf (3,603.8 J)
|| 2279 ft·lbf (3,089.9 J)
|| 1945 ft·lbf (2,637.1 J)
|| 1650 ft·lbf (2,237.1 J)
|| 1392 ft·lbf (1,887.3 J)
|| 1166 ft·lbf (1,580.9 J)
|.30-06 Springfield (Remington - PRA3006B) 165 gr
|| 2800 ft/s (853.4 m/s)
|| 2597 ft/s (791.6 m/s)
|| 2403 ft/s (732.4 m/s)
|| 2217 ft/s (675.7 m/s)
|| 2039 ft/s (621.5 m/s)
|| 1870 ft/s (570 m/s)
|| 2872 ft·lbf (3,893.9 J)
|| 2470 ft·lbf (3,348.9 J)
|| 2115 ft·lbf (2,867.6 J)
|| 1800 ft·lbf (2,440.5 J)
|| 1523 ft·lbf (2,064.9 J)
|| 1281 ft·lbf (1,736.8 J)
|.300 Winchester Magnum (Winchester - SXP300WM) 180 gr
|| 3000 ft/s (914.4 m/s)
|| 2819 ft/s (859.2 m/s)
|| 2646 ft/s (806.5 m/s)
|| 2479 ft/s (755.6 m/s)
|| 2318 ft/s (706.5 m/s)
|| 2163 ft/s (659.3 m/s)
|| 3597 ft·lbf (4,876.9 J)
|| 3176 ft·lbf (4,306.1 J)
|| 2797 ft·lbf (3,792.2 J)
|| 2455 ft·lbf (3,328.5 J)
|| 2147 ft·lbf (2,910.9 J)
|| 1869 ft·lbf (2,534 J)
|.300 Weatherby Magnum (Weatherby - N300180ACB) 180 gr
|| 3250 ft/s (990.6 m/s)
|| 3051 ft/s (929.9 m/s)
|| 2861 ft/s (872 m/s)
|| 2678 ft/s (816.3 m/s)
|| 2503 ft/s (762.9 m/s)
|| 2335 ft/s (711.7 m/s)
|| 4223 ft·lbf (5,725.6 J)
|| 3721 ft·lbf (5,045 J)
|| 3271 ft·lbf (4,434.9 J)
|| 2868 ft·lbf (3,888.5 J)
|| 2505 ft·lbf (3,396.3 J)
|| 2179 ft·lbf (2,954.3 J)
| Values courtesy of respective manufacturers
The .30 caliber is the most popular caliber in the United States. So it is not surprising that the widest range of bullets available is in the .30 caliber. The most useful bullet weights for the .300 Winchester Magnum are those weighting between 150 gr. However, bullets weighing between 110 gr are available to the reloader for the .300 Winchester Magnum.
Compared with the 30-06 Springfield the .300 Winchester Magnum provides about 300 ft/s (91.4 m/s). This translates to about 20% greater energy advantage over the 30-06 Springfield cartridge. Due to the short neck, heavier bullets particularly those of weighting greater than 200 gr and mono-metal bullets such as the Barnes X bullets will need to be seated more deeply into the cartridge. As the bullet will take up volume which could have be taken by the propellant velocity advantages diminish as the weight of the bullet increases.
The .300 Winchester Magnum is known for its accuracy and has been used for 1000 yards (914.4 m) and 1000 metres (1,093.6 yd) competitions. While in hunting situations such accuracy is unnecessary, such accuracy does aid in the extending the range of the cartridge. Taken together with its performance it remains one of the most useful and popular cartridge today.
Although cartridges such as the .30-378 Weatherby Magnum
The .30-378 Weatherby Magnum is a cartridge introduced by Weatherby in 1996 that uses the same case as the previously existing .378 Weatherby Magnum and .460 Weatherby Magnum, necked down to a 30 caliber bullet. It is offered with bullets between 165 and 200 grains in factory loading, generating...
, .300 Remington Ultra Magnum
The .300 Remington Ultra Magnum, also known as the .300 Ultra Mag or .300 RUM is a 7.62 mm caliber rifle cartridge , 7.62x72mm, or .30 caliber rifle cartridge introduced by Remington Arms in 1999. The .300 Remington Ultra Magnum is one of the largest commercially available .30 caliber magnums...
and the .300 Weatherby Magnum all exceed performance of the .300 Winchester Magnum none of these cartridges can be chambered in a standard length action. Few .30 caliber (7.62 mm) standard length cartridges can match the performance and versatility of the .300 Winchester Magnum.
The down side to this performance is recoil. The amount of recoil the cartridge generates is a step up from the non-magnum .30 caliber (7.62 mm) cartridges. Its recoil is about 40% greater than that of the .30-06 Springfield, which is known as a 'stout' cartridge. This would put the .300 Winchester Magnum at the upper limit of what most shooters can shoot comfortably for extended shooting sessions. As a rough comparison, the recoil of the .300 Winchester Magnum is roughly comparable to a 12 gauge shotgun shooting 1 oz. slugs. This greater recoil can make the .300 Winchester Magnum, despite its accuracy advantages, a harder cartridge to shoot actually accurately, when compared to non-magnum 30 caliber cartridges such as the .30-06 Springfield or the .308 Winchester. On the other hand, recoil is subjective (some are more sensitive to it than others) and one can get used to it with practice. Also, many rifles available today now have effective recoil attenuating features built in to them, such as muzzle compensators and energy absorbing stocks and butt-pads, that can significantly lessen recoil as it is felt by the shooter.
Sporting Applications and Usage
The .300 Winchester Magnum has enough power to spare against all species of ungulate. It is particularly useful when hunting the members of the ungulate family such as elk and moose and is a popular cartridge among hunters for these big game species. Elk can weigh as much as 1000 pounds (453.6 kg) and moose 1400 pounds (635 kg). Bullet weights of 165 gr are the preferred choices for these game species. Controlled expansion bullets such as the Nosler Partition or Barnes X are preferred rather than more lightly constructed bullets for these larger species of ungulate. Bullets weighting 150 gr are adequate for smaller deer such as the mule deer and white tail deer.
The .300 Winchester Magnum is an excellent cartridge for the hunting of sheep, as long range shooting circumstances can present themselves. With its velocity, low bullet drop and ability to retain usable energy at an extended range, the .300 Winchester Magnum comes into its element when hunting sheep. Be it for bighorn in the Rockies, argali in the Pamirs or mouflon in the Caucasus the cartridge is an excellent choice for the sheep hunter.
The .300 Winchester Magnum makes a good bear rifle. Both the black and grizzly bears are hunted using the cartridge. However,the grizzly bears is currently a protected species in the United States under the endangered species act. The grizzly bear can grow to be twice as large as the black bear and are among the largest predators. The Alaskan brown bear and the polar bear are the largest carnivores. Many consider the .300 Winchester Magnum to be on the lighter side of what is required for the largest bears but year in year out hunters have had success with the cartridge against these large bruins.
The cartridge is one of the more favored cartridge for African plains game. Its ability to shoot flat and carry its energy efficiently with bullets of good sectional density and ballistic coefficients provides the cartridge the long range performance necessary to take these game species at extended ranges. The .300 Winchester Magnum can be used to hunt everything from the dik-dik to the giant eland. It is an excellent cartridge choice for all plains game under 1500 pounds (680.4 kg).
The .300 Win Mag is a cartridge for big game hunting
Big game hunting is the hunting of large game. The term is historically associated with the hunting of Africa's Big Five game , and with tigers and rhinos on the Indian subcontinent. In North America, animals such as bears and bison were hunted...
and long-range shooting. It sees use in long-range benchrest shooting
Benchrest shooting is a sport in which very accurate and precise rifles are shot at paper targets from a rest or bench from a sitting position. Benchrest shooters are notoriously detail-oriented and constantly trying to further the accuracy potential of the rifle through experimentation. Nearly...
competitions and has been adopted by law enforcement marksmen and by a few specific branches of the U.S. Military for use by snipers. Maximum effective range is generally accepted to be 1210 yards (1,106.4 m) with ammunition incorporating low-drag projectiles. Sub 1 minute-of-angle (MOA
Minute of angle is the measurement of a ballistic round's deviation from its initial heading due to gravity and/or the effect of air resistance on velocity. Informally known as a "Bullet's Trajectory" or "the rainbow effect". Long range weapons must account for this effect because a fired round...
) accuracy out to 1000 yards (914.4 m) is not unusual in precision-built rifles firing match-grade ammunition. Velocity with a 180 gr projectile at a maximum powder charge and 24 inches (61 cm) barrel is 2975 ±.
Recoil from the .300 Win Mag is higher than the well-known .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...
, which owes its popularity in part to the fact that it it represents the upper limit of recoil that the typical shooter can manage without discomfort. Remington has made low-recoil rounds called "Managed-Recoil" available for the .300 Win Mag, which recoil less and provide performance similar to the .30-06 Springfield.
Military and Law Enforcement Applications
The U.S. government purchased MK 248 MOD 1 .300 Winchester Magnum
match-grade ammunition in 2009 for use in adapted M24 Sniper Weapon System
The XM2010 Enhanced Sniper Rifle , formerly known as the M24 Reconfigured Sniper Weapon System, is a sniper rifle developed by PEO Soldier for the U.S. Army. It is derived from the M24 Sniper Weapon System and is intended to replace existing M24s. After winning a competitive bidding process,...
s and other .300 Winchester Magnum sniper rifles like the U.S. Navy Mk.13s. This ammunition was developed as a .300 Winchester Magnum Match Product Improvement (PIP) and uses the 220 gr (14.26 g) Sierra MatchKing Hollow Point Boat Tail (HPBT) very-low-drag bullet
Very-low-drag bullets are primarily a small arms ballistics development of the 1980s–1990s, driven by shooters' desire for bullets that will give a higher degree of accuracy and kinetic efficiency, especially at extended ranges. To achieve this the projectile must minimize air resistance in flight...
fired at a nominal muzzle velocity of 2,850 ft/s plus or minus 50 ft/s (869 m/s ± 15.2 m/s). According to the U.S. Navy this ammunition should increase the maximum effective range of .300 Winchester Magnum sniper rifle systems to 1,500 yards (1,370 m), decrease wind deflection on bullets in flight and use a reduced muzzle flash propellant that remains temperature stable across an operational temperature range of -25 °F to +165 °F (-32 °C to 74 °C).
Several companies, among them HS precision, Kimber and Remington manufacture rifles chambered for the .300 Winchester Magnum specifically targeted at law enforcement agencies. The Chattanooga Police Department and Minot Police Department S.W.A.T units and the L.A. County Sheriffs Department's Special Enforcement Bureau which have adopted the .300 Winchester Magnum in some capacity. Due to the power and performance of the .300 Winchester Magnum cartridge the cartridge is more likely to be employed by specialist units within a police department rather than as a general service weapon issued to law enforcement agents.
Military & Law Enforcement platforms
- Sako TRG-41
Sako TRG-22/42 sniper rifles were developed by the Finnish firearm manufacturer SAKO of Riihimäki. The TRG-22 is designed to fire standard .308 Winchester ammunition, while the TRG-42 is designed to fire more powerful .300 Winchester Magnum and .338 Lapua Magnum ammunition and therefore has a...
- Bundeswehr G22 - Accuracy International L96A1
The AWM is a sniper rifle manufactured by Accuracy International. It is also known as the AWSM , which typically denotes the .338 Lapua Magnum version.-The Arctic Warfare Magnum system:...
- Mk.13 Sniper Weapon System - M86 sniper rifle
The M86 sniper rifle is a bolt action sniper rifle that was used by the U.S. armed forces and manufactured by Harris Gunworks . It was used by Navy SEALs and Delta Force...
- Armalite Model AR-30 - Remington 700|Remington Model 700 Police Long Action tactical rifle - Savage Model 110BA - Weatherby TRR Threat Response Rifle
The .300 Winchester Magnum was designed with a neck which is shorter than the diameter of its bullet. If Winchester had released the cartridge prior to 1960 the cartridge would have been similar to the .30-338 Winchester wildcat cartridge. However, by the time Winchester got around to designing their own .300 the .308 Norma Magnum and the .30-338 were already on the scene. To help differentiate it from the other .300 magnums and to allow for the chambers of the standard length .300 magnums to be rebored to the .300 Winchester Magnum chamber dimensions, Winchester moved the shoulder forward and lengthened the cartridge slightly. This created the long criticized short neck of the .300 Winchester Magnum.
The short neck was thought to hinder accuracy because it would prevent the alignment of cartridge to the bore but this is rarely an issue either today or when the cartridge was designed. The fact that the cartridge has gone to win many 1000 yards (914.4 m) matches puts this criticism to rest.
However, the short neck with the shoulder moved forward does cause some real problems. Since the .300 Winchester Magnum is designed to work out of a standard length action heavier bullets will need to be seated deeper into the case. Since many heavier .30 caliber (7.62 mm) bullets have a long taper, and these bullets will be required to be seated deeper into the case, the neck will end up being positioned in the ogive rather than on the shank of the bullet due to the fact that Winchester had moved the shoulder forward. This prevents the case from having a good grip on the bullet. Under recoil such loosely held bullets in the magazine will be pushed back into the case. Also, if using a highly compressed load the cartridge might “grow” in length and may not be able to fit into the magazine. For these reasons bullets weighing over 200 gr are not recommended. Norma goes further recommending that bullets heavier than 180 gr not be used with the cartridge.
- List of rifle cartridges
- 7 mm caliber
This article lists firearm cartridges which have a bullet in the to caliber range.*Length refers to the cartridge case length.*OAL refers to the overall length of the cartridge....
- List of individual weapons of the U.S. Armed Forces
- Sectional density
Sectional density is the ratio of an object's mass to its cross-sectional area. It conveys how well an object's mass is distributed to overcome resistance. For illustration, a needle can penetrate a target medium with less force than a coin of the same mass...