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.264 Winchester Magnum

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.264 Winchester Magnum
.264 Winchester Magnum
TypeRifle
Place of originUnited States
Production history
DesignerWinchester
Designed1959
ManufacturerWinchester
Specifications
Bullet diameter.264 in (6.7 mm)
Neck diameter.299 in (7.6 mm)
Shoulder diameter.491 in (12.5 mm)
Base diameter.515 in (13.1 mm)
Rim diameter.532 in (13.5 mm)
Case length2.5 in (64 mm)
Overall length3.34 in (85 mm)
Rifling twist1:9
Primer typeLarge rifle
Maximum pressure64,000 psi (440 MPa)
Ballistic performance
Bullet mass/type Velocity Energy
100 gr (6 g) Nosler Ballistic Tip 3,510 ft/s (1,070 m/s) 2,735 ft⋅lbf (3,708 J)
125 gr (8 g) Nosler Partition 3,180 ft/s (970 m/s) 2,806 ft⋅lbf (3,804 J)
140 gr (9 g) BTSP 3,200 ft/s (980 m/s) 3,183 ft⋅lbf (4,316 J)
Source(s): Conley Precision Cartridge [1]

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 (2.5 in (64 mm)) Holland & Holland belted magnum case. It was introduced together with the .338 Winchester Magnum and the .458 Winchester Magnum as one of a series of short-cased (2.5 in (64 mm)) belted magnum cartridges developed by Winchester. It was officially introduced to the public by Winchester in 1959.

Design & Specifications

Winchester had been manufacturing the shortened Holland & Holland cases under a contract for Weatherby for use in their .257 Weatherby Magnum, .270 Weatherby Magnum and 7mm Weatherby Magnum cartridges. While the Weatherby cases had been based on the Winchester's .30 Super cartridge, these new series of shortened Holland & Holland cases were based on the .375 Holland & Holland case which was more plentiful and hence more available. The advantages of the shortened case were two fold: the cartridge could function through the easily available standard length rifle action used by the .30-06 Springfield and the .270 Winchester and was close to the efficiency limitations of powders available at the time given the case capacity of the cartridge. Using the longer, full length .375 H&H case would not have produced a great performance benefit given the powders available. This was also the reasoning behind the shortened cases used by Weatherby as DuPont's IMR 4350 had been the slowest burning powder available at the time.

The .264 Winchester Magnum is a cartridge which was standardized by SAAMI, which published recommended specifications for the cartridge. SAAMI recommends a six groove barrel with a rate of twist of one revolution in 9 in (230 mm), a bore diameter of .256 in (6.5 mm) and a groove diameter of .264 in (6.7 mm) with each groove having a width of 0.090 in (2.3 mm). The recommended maximum pressure for the cartridge (pizeo) is 64,000 psi (4,400 bar).

Performance

The .264 Winchester Magnum gained a reputation as a very flat shooting cartridge. When introduced, it was first chambered in the Winchester Model 70 Westerner rifle, which was intended for longer range shooting more common in the Western United States.

At present, only Remington and Winchester produce ammunition for this cartridge and then only in their non-premium economy line, Express and Super-X respectively. Both manufacturers offer a 140 gr (9.1 g) bullet at 3,030 ft/s (920 m/s). This ammunition has a maximum point blank range of 299 yd (273 m) when sighted in at 249 yd (228 m). Double Tap Ammunition offers premium 140 gr (9.1 g) Nosler Partition and 125 gr (8.1 g) Accubond bullets driven at 3,100 ft/s (940 m/s) and 3,250 ft/s (990 m/s) through a 24-inch (610 mm) barrel. However, Double Tap is available only through mail order and select dealers.

While readily available factory ammunition for the cartridge is for the most part fairly basic, the handloaders can gain a step up in performance with bullets with better ballistic coefficients and weights to extend to performance of the cartridge. For this reason, this cartridge is better suited for shooters who are willing to make their own ammunition rather than those who purchase over the counter ammunition.

Reception

The .264 Winchester Magnum main competition comes from the various 7mm cartridges such as the 7mm Remington Magnum, 7mm Weatherby Magnum, the .270 Winchester Short Magnum, .270 Weatherby Magnum, 6.5mm Remington Magnum and the .257 Weatherby Magnum cartridges in North America and the cartridges such as the 6.5x68mm in Europe. Due to the over crowded nature of the market for which the cartridge competes in, popularity has been on the wane. In particular, the 7mm Remington Magnum release in 1962 lead to the cartridge's poor reception by the shooting public. The 7mm Remington Magnum shot almost as flat as the .264 Winchester Magnum but launched a larger diameter, heavier bullet generating more energy than the .264 Winchester Magnum. Furthermore, the 7mm Remington Magnum benefited from a vast range of compatible bullets due in large part to the popularity while the .264 was somewhat of an oddity and a rather "new" caliber in North America.

Ballistically, it is almost identical to the 6.5 x 68 (also incorrectly known as the 6.5 x 68 RWS, 6.5 x 68 Schüler or the 6.5 x 68 Express Vom Hofe) and the 6.5 x 63 Messner Magnum.

The .264 Win. Mag. is an excellent, potentially accurate, very flat-shooting cartridge capable of taking any game in the lower 48 US states, and one of the most powerful of all .264 in (6.7 mm) cartridges. When loaded with 140 gr (9.1 g) bullets at a muzzle velocity of 3,100 ft/s (940 m/s) it is an adequate round for deer out to beyond 500 yards (460 m) provided that the hunter is capable of such longer shots.

Background

The .264 Win. Mag., like many magnum rounds, can wear out barrels more quickly than other rounds.[2] This was particularly true in the 1950s to early 1960s, with the chrome moly steels then almost universally used for barrels. But recent advances with stainless steel barrels, especially when cryogenically treated, have extended barrel life considerably, with the .264 Win. Mag. and many other cartridges.[citation needed]

While very few production line riflemakers currently offer the .264 Win. Mag. as a factory chambering, the caliber remains popular with some enthusiasts using custom built rifles and handloading their own ammunition.[citation needed]

The introduction of Remington's 7 mm Magnum in 1962 almost immediately eclipsed the .264 Win. Mag., even though the 264 Win. Mag. uses an identical brass cartridge case (the neck diameter of either cartridge case can easily be modified to accept the others' bullets by the handloader), it never fully recovered from the competition of the slightly larger-bore cartridge.[3][4]

The fact that the 7 mm Rem. Mag. thoroughly eclipsed its popularity has been attributed to many causes, the premature "burning out" of barrels as compared to the Remington cartridge often cited. More likely is the fact that hunters had more confidence in the game-getting ability of heavier 7 mm (.284") 150 to 175 grain spitzer-shaped projectiles on big game, as compared to 140 grains being the upper end of pointed .264 bullets.

Conversely, Winchester marketed the .264 as a long range, combination varmint and deer round, although suited for harvesting the occasional elk or moose. Unfortunately, the recoil it generates, plus the expense of the sheer quantity of ammo that may be used to shoot pests at long range (compared to pure varmint cartridges like the .222 Remington and the .220 Swift, or the smaller varmint / deer rounds, like the .243 Winchester) inhibited its popularity further. The result was more sportsmen opting for the bigger Remington 7 mm round because it was seen as more effective on wider variety of big game; rather than a compromise round that could be used for varmints, worked well on whitetail and mule deer, but was borderline for the largest North American big game should the need arise.

In Europe, two of the .264 Win. Mag.'s champions were George Swenson of John Wilkes gunmakers, London, and David Lloyd of Northampton, England. Lloyd built a number of his deluxe Lloyd rifles in .264 Win. Mag. calibre, mainly for sportsmen seeking a calibre that would give high velocity performance with bullets heavier than the 100 grains fired by the .244 H&H Magnum.

See also

References

  1. ^ Conley Precision Cartridge ballistics table
  2. ^ Edward A. Matunas; Ed Matunas (2003). Do-It-Yourself Gun Repair. Woods N Water Inc. ISBN 0-9722804-2-1.{{cite book}}: CS1 maint: multiple names: authors list (link)
  3. ^ 2002, Lyman's Reloading Handbook, 48th Edition
  4. ^ .264 Winchester Magnum info and loading data from Accurate Powder