.260 Remington
| .260 Remington | ||||||||||||
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.260 Remington cartridge with a 120 grain Remington Core-Lokt bullet.
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| Type | Rifle | |||||||||||
| Place of origin | United States | |||||||||||
| Production history | ||||||||||||
| Manufacturer | Remington Arms Company | |||||||||||
| Produced | 1997 | |||||||||||
| Specifications | ||||||||||||
| Parent case | .308 Winchester | |||||||||||
| Bullet diameter | .264 in (6.7 mm) | |||||||||||
| Neck diameter | .2969 in (7.54 mm) | |||||||||||
| Shoulder diameter | .4539 in (11.53 mm) | |||||||||||
| Base diameter | .4705 in (11.95 mm) | |||||||||||
| Rim diameter | .4728 in (12.01 mm) | |||||||||||
| Rim thickness | .0539 in (1.37 mm) | |||||||||||
| Case length | 2.035 in (51.7 mm) | |||||||||||
| Overall length | 2.800 in (71.1 mm) | |||||||||||
| Rifling twist | 1-9 inches (228.6 mm) | |||||||||||
| Primer type | Large rifle | |||||||||||
| Maximum pressure (C.I.P.) | 60,190 psi (415.0 MPa) | |||||||||||
| Maximum pressure (SAAMI) | 60,000 psi (410 MPa) | |||||||||||
| Ballistic performance | ||||||||||||
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| Source(s): Remington Arms Co. ballistics table | ||||||||||||
The .260 Remington (also known as 6.5-08 A-Square) cartridge was introduced by Remington in 1997. Many wildcat cartridges based on the .308 Winchester case had existed for years before Remington standardized this round. Although loaded to higher pressures, the ballistics of this cartridge are basically similar to the 6.5×55mm when bullet weights do not exceed 140 grains. When loaded with heavier bullets, the 6.5×55mm is capable of greater velocity. Due to its shorter overall length the .260 Remington can be chambered in a shorter length action than the 6.5×55mm.
Because 6.5 mm (.264") bullets have relatively high ballistic coefficients, the .260 Remington has seen success in rifle competition including bench rest, Metallic Silhouette and long range. It is capable of duplicating the trajectory of the .300 Winchester Magnum while generating significantly lower recoil. Also, converting a rifle chambered for the .308 Winchester (or any of its offspring, such as the 6.5 Creedmoor, .243 Winchester, 7mm-08 Remington or .338 Federal) to .260 Remington generally requires little more than a simple barrel change.
Remington has had a track record of adopting successful wildcat cartridges into the Remington fold by offering rifles and ammunition and at times attaching their name to the cartridge. Like many cartridges such as the .22–250 Remington, .25-06 Remington and the 7 mm-08 Remington, the .260 Remington started its life as a wildcat cartridge called the 6.5-08 and was eventually released as a commercial cartridge by Remington. However, it was not Remington who first attempted to standardize the cartridge. LTC Arthur Alphin and his company A-Square LLC submitted the first proposal and drawings to SAAMI for the standardization of the cartridge. Remington was to file similar papers with SAAMI to do the same a few months later. When the dust settled it was found that the 6.5-08 would be called the .260 Remington instead of 6.5–08 A-Square.
The 6.5 -08 cartridge was created simply by necking down the .308 Winchester.Handloaders and wildcatters can easily form .260 cases by necking down the 7mm-08 Remington or necking up the .243 Winchester (both based on the same .308 case). Since the parent cartridges were readily available for low cost, the 6.5 -08 was often an economical alternative to cartridges such as the 6.5×55mm. What the 6.5-08 provided over the .243 Winchester, .308 Winchester and to a lesser degree the 7mm-08 Remington was bullets with excellent ballistic coefficients and sectional densities relative to their weights.
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