.264 Winchester Magnum

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.264 Winchester Magnum
Type	Rifle
Place of origin	United States
Production history
Manufacturer	Winchester
Produced	1959
Specifications
Bullet diameter	.264 in (6.71 mm)
Neck diameter	.299 in (7.59 mm)
Shoulder diameter	.491 in (12.47 mm)
Base diameter	.515 in (13.08 mm)
Rim diameter	.532 in (13.51 mm)
Case length	2.5 in (63.5 mm)
Overall length	3.34 in (84.84 mm)
Rifling twist	1:9
Primer type	Large rifle
Ballistic performance
Bullet weight/type	Velocity	Energy
100 gr Nosler Ballistic Tip	3510 ft/s (~1070 m/s)	2735 ft·lbf (~3720 J)
125 gr Nosler Partition	3180 ft/s (~970 m/s)	2806 ft·lbf (~3816 J)
140 gr BTSP	3200 ft/s (~976 m/s)	3183 ft·lbf (~4329 J)
Source: Conley Precision Cartridge ballistics table

The .264 Winchester Magnum is one of a series of short-cased (2.5in.) belted magnum cartridges developed by Winchester, and officially introduced to the public by them in 1959.

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 Von Hofe Express).

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 .264in/6.5mm cartridges. When loaded with 140 grain bullets at a muzzle velocity of 3,100 fps. it is a very adequate round for deer out to 500 yards.

The .264 Win. Mag. has had a reputation for being hard on barrels, and it can wear them out in as few as 500 rounds, especially if long strings of shots are fired with an increasingly warm barrel. In the late 1950's - early 1960's this was particularly true 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.

While very few production line riflemakers now (2007) offer the .264 Win. Mag. as a factory chambering, this calibre remains popular with some enthusiasts using custom built rifles and handloading their own ammunition.

The introduction of Remington's 7 mm Magnum in 1962 almost immediately eclipsed the .264 Win. Mag., and it never fully recovered from the competition of the slightly larger-bore cartridge.^[1]

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 de-luxe 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.

The 264 Win. Mag., when loaded with 129 grain bullets, gives quite moderate recoil, but with 140 grain bullets recoil increases significantly, although a good recoil pad fitted to the rifle will reduce sensible recoil before it gets to your shoulder.

.264 Win. Mag. barrel specifications: Rifling Twist Rate 1 : 9 Bore Groove Diameter .263in

.264 Win. Mag. reloading specifications: Bullet Diameter .264in Maximum Case Length 2.500in Trimmed Case Length 2.490in Primer Size : Large Rifle