.270 Winchester

Left to Right 130-grain (8.4 g) - Hollow Point, 100-grain (6.5 g) FMJBT, 130-grain (8.4 g) Soft point, 160-grain (10 g) Lead round nose.

Type

Rifle / Hunting

Place of origin

United States

Production history

Designer

Winchester

Designed

1923

Manufacturer

Winchester

Produced

1925-Present

Specifications

Parent case

.30-06

Bullet diameter

.277 in (7.0 mm)

Neck diameter

.308 in (7.8 mm)

Shoulder diameter

.441 in (11.2 mm)

Base diameter

.470 in (11.9 mm)

Rim diameter

.473 in (12.0 mm)

Case length

2.540 in (64.5 mm)

Overall length

3.340 in (84.8 mm)

Case capacity

67 gr H₂O (4.3 cm³)

Rifling twist

1 in 10 in (250 mm)

Primer type

Large rifle

Maximum pressure

65,000 psi (450 MPa)

Ballistic performance

Bullet weight/type	Velocity	Energy
90 gr (6 g) HP	3,603 ft/s (1,098 m/s)	2,595 ft·lbf (3,518 J)
130 gr (8 g) SP	3,060 ft/s (930 m/s)	2,702 ft·lbf (3,663 J)
140 gr (9 g) SP	2,916 ft/s (889 m/s)	2,644 ft·lbf (3,585 J)
150 gr (10 g) SP	2,850 ft/s (870 m/s)	2,706 ft·lbf (3,669 J)
130 gr (8 g) SST	3,200 ft/s (980 m/s)	2,955 ft·lbf (4,006 J)

Source(s): Hodgdon,^[1] Hornady^[2]

The .270 Winchester (or 6.9x64mm) was developed by Winchester Repeating Arms Company in 1923 and unveiled in 1925 as a chambering for their bolt-action Model 54.^[3] The cartridge is a necked down .30-06 Springfield. When loaded with a bullet that expands rapidly or fragments in tissue, this cartridge delivers devastating terminal performance.^[4]^[5]^[6]

Description

The .270 Winchester became a very popular deer and elk cartridge due to the widespread praises of gunwriter Jack O'Connor who used the cartridge for 40 years and espoused its merits in the pages of Outdoor Life.^[7]^[8] It drives an 8.4 grams (130 gr) bullet at approximately 960 m/s (3,140 ft/s), later reduced to 930 m/s (3,060 ft/s). The cartridge demonstrated high performance at the time of its introduction and was marketed as being suitable for big game shooting in the 370 to 910 metres (400 to 1,000 yd) range. Two additional bullet weights were soon introduced: a 6.5 grams (100 gr) hollow-point bullet for varmint shooting, and a 9.7 grams (150 gr) bullet for larger deer, elk and moose in big-game hunting.^[3]

While not an immediate success, over the succeeding decades and especially in the post-World War II period, the .270 Winchester attained great popularity among gun owners and hunters, ranking it among the most popular and widely used cartridges worldwide. Internationally, firearms manufacturers now offer this chambering in all firearm varieties: bolt-actions, single-shots, lever-actions (such as Browning BLR), pump-actions (such as Remington 7600), autoloaders (such as Remington 7400) and even a few double rifles.^[9]

Loads

Loads are commonly available from 6.5 to 10.4 grams (100 to 160 gr), sizes with 8.4-and-9.7-gram (130 and 150 gr) loads being by far the most popular. Handloaders have a larger range of options with the availability of bullets in a number of weights from 5.8 to 11.7 grams (90 to 180 gr). Common bullet weight recommendations for shooting different game are as follows:

5.8–7.1 grams (90–110 gr) bullets: animals smaller than coyote.
8.4 grams (130 gr) bullets: antelope or other animals up to the size of mule deer.
9.1–10.4 grams (140–160 gr) bullets: deer, elk, moose and some larger animals.^[1]

Recent introductions of low-drag bullets suited to the 270 Winchester such as the Nosler Accubond Long-Range and Matrix long range bullets are promoting renewed interest in the cartridge among long range hunters.

While it is true that a .270 Winchester case can be formed from a 30-06 Springfield case, the case length of a 30-06 is 63.3 millimetres (2.494 in) while the case length of a .270 is 64.5 millimetres (2.540 in), the same as a .30-03 Springfield. It is recommended that .270 Winchester brass be formed from .35 Whelen or .280 Remington cases.^[10]

.270 Winchester cartridge

References

1 2 .270 Win data from Hodgdon
↑ Hornady Superformance commercial ammo specifications
1 2 The Complete Reloading Manual for the .270 Winchester, Loadbooks USA, Inc., 2004, pp.13,19
↑ Chamberlin FT, Gun Shot Wounds, in Handbook for Shooters and Reloaders, Vol. II, Ackley PO, ed., Plaza Publishing, Salt Lake City, Utah, 1966.
↑ Scientific Evidence for Hydrostatic Shock
↑ Shooter’s Bible, Robert F. Scott, p. 28
↑ Barnes Reloading Manual Number 2 (1997)
↑ Hornady Handbook of Cartridge Reloading, Fourth Edition (1996)
↑ Speer Reloading Manual Number 12 (1994)
↑ .270 Cartridge dimensions

Winchester firearms and cartridges

Rifles

Lever-action	Henry rifle Model 1866 Model 1873 Model 1876 Model 1886 Model 1892 Model 1894 Model 1895 Model 53 Model 55 Model 64 Model 65 Model 71 Model 88 Model 150 Model 250 Model 255 Model 9422

Bolt-action	Model 1878 Hotchkiss Model 1895 Lee Navy Model 1900 Model 1902 Model 1904 Model 43 Model 47 Model 51 Imperial Model 52 Model 54 Model 56 Model 57 Model 58 Model 59 Model 60 Model 60A Model 67 Model 68 Model 69 Model 70 Model 72 Model 75 Model 121 Model 131 Model 141 Model 320 Model 325 Model 670 Model 770

Pump-action	Model 1890 Model 1906 Model 61 Model 62 Model 62A Model 270

Semi-automatic	Model 1903 Model 1905 Model 1907 Model 1910 Model 30 Model 63 Model 74 Model 77 Model 100 Model 190 Model 490

Full-automatic	Olin/Winchester FAL Model 1917

Falling-block action	Model 1885

Shotguns

Pump-action	Model 1893 Model 1897 Model 1912 Model 25 Model 42 Model 1200 Model 1300

Lever-action	Model 1887 Model 1901 Model 9410

Single-shot	Model 20 Model 36 Model 37 Model 37A Model 41

Double-barrel	Model 21 Model 24 Model 96 Model 101

Semi-automatic	Model 1911 SL Model 40 Model 50 Model 59 Model 1400 Model 1500 SX-1

Cartridges

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.270 Winchester

Description

Loads

See also

References