6.5mm Grendel
| 6.5mm Grendel | ||||||||||||||||||||||||
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6.5mm Grendel showing variety of bullets—144 gr (9.3 g) to 90 gr (5.8 g) | ||||||||||||||||||||||||
| Type | Rifle | |||||||||||||||||||||||
| Place of origin | United States | |||||||||||||||||||||||
| Production history | ||||||||||||||||||||||||
| Designer | Bill Alexander and Janne Pohjoispää | |||||||||||||||||||||||
| Designed | 2003 | |||||||||||||||||||||||
| Specifications | ||||||||||||||||||||||||
| Parent case | .220 Russian (5.6×39mm) | |||||||||||||||||||||||
| Case type | Rimless, bottleneck | |||||||||||||||||||||||
| Bullet diameter | 6.71 mm (0.264 in) | |||||||||||||||||||||||
| Land diameter | 6.50 mm (0.256 in) | |||||||||||||||||||||||
| Neck diameter | 7.44 mm (0.293 in) | |||||||||||||||||||||||
| Shoulder diameter | 10.87 mm (0.428 in) | |||||||||||||||||||||||
| Base diameter | 11.15 mm (0.439 in) | |||||||||||||||||||||||
| Rim diameter | 11.2 mm (0.44 in) | |||||||||||||||||||||||
| Rim thickness | 1.5 mm (0.059 in) | |||||||||||||||||||||||
| Case length | 38.7 mm (1.52 in) | |||||||||||||||||||||||
| Overall length | 57.5 mm (2.26 in) | |||||||||||||||||||||||
| Case capacity | 2.3 cm3 (35 gr H2O) | |||||||||||||||||||||||
| Rifling twist | 1 in 200 mm (8 in) or 1 in 230 mm (9 in) | |||||||||||||||||||||||
| Primer type | Small rifle | |||||||||||||||||||||||
| Maximum pressure | 360 MPa (52,000 psi) | |||||||||||||||||||||||
| Ballistic performance | ||||||||||||||||||||||||
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| Test barrel length: 24 inches (610 mm) Source(s): Alexander Arms Pressure-safe Load Data | ||||||||||||||||||||||||
The 6.5mm Grendel (6.5×38mm) is an intermediate cartridge jointly designed by British-American armorer Bill Alexander, competitive shooter Arne Brennan (of Houston, Texas) and Lapua ballistician Janne Pohjoispää, as a low-recoil, high-precision rifle cartridge specifically for the AR-15 platform at medium/long range (200–800 yard). It is an improved variation of the 6.5mm PPC.
The 6.5mm Grendel cartridge was first unveiled in May 2003 at the Blackwater Training Facility in North Carolina, where it remained supersonic at 1,200 yd (1,100 m) range and out-shot the 7.62mm NATO with only half the recoil. Since its introduction, it has proven to be a versatile cartridge and is now expanding into other firearm design platforms including bolt-action rifles and the Kalashnikov system.
The name "Grendel" is inspired by the mythical monster antagonist from the Old English epic poem Beowulf. It was a trademark owned by Alexander Arms (Bill Alexander's company in Radford, Virginia) and manufactured at Radford Arsenal, until legally released in 2010 for SAAMI standardization with collaboration from Hornady.