.256 Newton

Type

Hunting

Place of origin

United States

Production history

Designer

Charles Newton

Designed

1913

Manufacturer

Western Cartridge Company

Specifications

Parent case

.30-06 Springfield

Case type

Rimless

Bullet diameter

.264 in (6.7 mm)

Neck diameter

.291 in (7.4 mm)

Shoulder diameter

.418 in (10.6 mm)

Base diameter

.471 in (12.0 mm)

Rim diameter

.473 in (12.0 mm)

Rim thickness

.049 in (1.2 mm)

Case length

2.440 in (62.0 mm)

Overall length

3.40 in (86 mm)

Rifling twist

1 in 10"

Primer type

large rifle

Ballistic performance

Bullet mass/type	Velocity	Energy
123 gr (8 g)	3,103 ft/s (946 m/s)	2,632 ft·lbf (3,569 J)
140 gr (9 g)	3,000 ft/s (910 m/s)	2,800 ft·lbf (3,800 J)

Source(s): Newton Arms Company Catalog. 14th edition, 1920. IN Barnes, Frank C. "Cartridges of the World" Digest Books Inc., 1972.

The .256 Newton is a high-velocity rimless cartridge and was developed by Charles Newton in 1913 in conjunction with the Western Cartridge Company. It is a 30-06 Springfield cartridge, shortened and necked down to .264) with a different shoulder angle. However, the .256 Newton and the .30-06 are not interchangeable. The .256 Newton and the 6.5-06 are not interchangeable.

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