6.5mm Creedmoor

Size comparison of short-action cartridges, left to right: (AR-10 length, approx max length 2.8" or 71.5 mm) .308 Winchester, 6.5mm Creedmoor, .243 Winchester, (AR-15 length) 6.5mm Grendel, .223 Remington

Type

Centerfire rifle

Place of origin

United States

Production history

Designed

2007

Manufacturer

Hornady

Produced

2008

Specifications

Parent case

.30 TC

Case type

Rimless, bottleneck

Bullet diameter

.2644 in (6.72 mm)

Neck diameter

.2950 in (7.49 mm)

Shoulder diameter

.4620 in (11.73 mm)

Base diameter

.4703 in (11.95 mm)

Rim diameter

.4730 in (12.01 mm)

Rim thickness

.054 in (1.4 mm)

Case length

1.920 in (48.8 mm)

Overall length

2.825 in (71.8 mm)

Case capacity

52.5 gr H₂O (3.40 cm³)

Rifling twist

1-8" (203 mm)

Primer type

Large rifle

Maximum pressure (C.I.P.)

63,100 psi (435 MPa)

Maximum pressure (SAAMI)

62,000 psi (430 MPa)

Ballistic performance

Bullet mass/type	Velocity	Energy
120 gr (8 g) AMAX	3,020 ft/s (920 m/s)	2,430 ft·lbf (3,290 J)
140 gr (9 g) Hornady ELD-X	2,710 ft/s (830 m/s)	2,283 ft·lbf (3,095 J)

Test barrel length: 28 inch
Source(s): Hornady, SAAMI, CIP

The 6.5mm Creedmoor, also called the 6.5 Creedmoor or 6.5 CM for short, is a centerfire rifle cartridge introduced by Hornady in 2007 as a modification of the .30 TC, which was based on the .300 Savage. It was designed specifically for rifle target shooting, although it is also achieving success in game hunting. Bullet for bullet, the 6.5mm Creedmoor achieves a slower muzzle velocity than longer cartridges such as the 6.5-284 Norma or magnum cartridges such as the 6.5mm Remington Magnum. However, due to its 2.825 inches (71.8 mm) overall length, it is capable of being chambered in short-action bolt action rifles and AR-10 semi-automatic rifles.

6.5 mm (.264") bullets, in general, are known for their relatively high sectional density and ballistic coefficients, and have seen success in rifle competition. For some loads the 6.5mm Creedmoor is capable of duplicating the muzzle velocity or trajectory of the .300 Winchester Magnum while generating significantly lower recoil, based on lighter projectile weight. As this cartridge is designed for a bolt face diameter of .473 inches (roughly 12 mm), conversion of a short action rifle to another caliber (such as the .22-250 Remington, .243 Winchester or .300 Savage) with similar bolt face diameter generally requires little more than a simple barrel change.

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Wikipedia