260 rem

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 .243 Winchester, 7mm-08 Remington, .358 Winchester or .338 Federal) to .260 Remington generally requires little more than a simple barrel change.

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