6.5mm Creedmoor

6.5mm Creedmoor

Size comparison of some 6.5mm cartridges, left to right: .264 Winchester Magnum, 6.5×55mm Swedish, .260 Remington, 6.5mm Creedmoor, 6.5mm Grendel
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,[1] SAAMI,[2][3] CIP[4][5]

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[6] as a modification of the .30 TC,[7] which was based on the .308 Winchester. It was designed specifically for rifle target shooting,[6] although it is also achieving success in game hunting.[7] 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.

Design considerations

6.5 mm (.264") bullets, in general, are known for their relatively high sectional density[7] and ballistic coefficients, and have seen success in rifle competition. For some loads the 6.5mm Creedmoor is capable of duplicating the muzzle velocity[2] or trajectory[8] 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.

Performance

This is a medium power cartridge often compared to the .260 Remington and 6.5×47mm Lapua but is not as accurate as the Lapua case.[9] Three hundred yard energy using 129 grain Hornady SST bullets is listed by an independent reviewer as 1641 ft. lbs.[10] For the 140 grain bullet at 2700 feet per second initial velocity another reviewer reports an MPBR[11] for a six inch high target of 265 yards and reports a manufacturer claim of "almost 1600 ft. lbs." of retained energy at 300 yards using a 24-inch barrel.[12] SAAMI test data confirms 6.5 mm Creedmoor (fifteen feet from muzzle) velocity of 2,940 fps for the 129 grain bullet and 2,690 for the 140 grain bullet (which compares to .300 Winchester magnum data of 2,930 fps for a 200 grain bullet and 2,665 fps for a 210 grain bullet).[2] Long-range shooter Ray "RayDog" Sanchez summarised the bolt-action Tubb 2000 rifle in 6.5mm Creedmoor as "boringly accurate" at 1000 yards (914.4 metres). He asserted the rifle and ammunition combination he used was able to maintain sub-MOA groups at 1000 yards (914.4 metres).[13] Lapua brass for 6.5mm Creedmoor is now available[14][15] and may improve accuracy for hand loaders, due to features such as a small primer pocket intended for industry standard small rifle primers[16] (as opposed to the industry-standard large rifle primer pocket[16] found in other manufacturer's creedmoor brass). Small rifle primers are also found in proven cartridges such as the 6PPC, 6BR, 6.5x47 and 308 PALMA. A small primer pocket is said to produce smaller extreme spread in muzzle velocity.

Handloading

Handloading cost for the 6.5 Creedmoor is roughly equivalent to other 6.5mm cartridges, such as the 6.5×47, due to the availability of Lapua small primer brass for both cartridges.[14][17] Norma now makes brass for the cartridge and as of 2017 Norma brass is available through several major retailers at approximately the same cost as Lapua brass. Lapua brass for 6.5×47 lasts about 12 to 20 reloads.[18] When the 6.5 CM was first introduced it was advertised as a 60,000 psi capable case.[6] However, when it was placed into production Hornady listed it as 62,000 psi and had it SAAMI registered as such. For this reason many hand loaders have had poor experiences reloading for it. Blown primers on the first shot at 62,000 psi is not uncommon. Early shooting articles listed the ammo as loaded to 58,000 psi[19] but later ones list it as 57,000 psi.[20] This is because Hornady reduced the loads in its factory ammo because of complaints that it was often blowing primers.[21] Lapua delivered Creedmoor brass at Shot show 2017,[22] and production quantities became available via major retailers in second quarter 2017. The Lapua version has a small primer pocket. Thus, loads from a Lapua Creedmoor should not be used in another manufacturer's Creedmoor brass that features a large primer pocket without applying proper hand loading test for pressure first. Also the use of a smaller diameter decapping rod is required to size and decap.

Only the very longest 140gr bullets will even reach the neck shoulder junction. Right to left: is a 123gr A-Max and Remington 140gr. Calipers are set to magazine length.

See also

Notes

  1. ↑ UPDATED: 135gr to 145gr is no longer available with 2500 ft-lb Hornady's 6.5CM section older: Hornady Manufacturing Company
  2. 1 2 3 ANSI/SAAMI Velocity & Pressure Data: Centerfire Rifle Archived 2013-07-15 at WebCite
  3. ↑ http://saami.org/specifications_and_information/publications/download/Z299-4_ANSI-SAAMI_CFR.pdf#page=51
  4. ↑ http://www.cip-bobp.org/homologation/uploads/tdcc/tab-i/6-5-creedmoor-en.pdf
  5. ↑ Shooting Times,
  6. 1 2 3 http://bulletin.accurateshooter.com/2007/11/hornady-introduces-new-65-creedmoor-cartridge/
  7. 1 2 3 Rupp, J. Scott (February 8, 2012). "The Versatile 6.5 Creedmoor". RifleShooter. Guns & Ammo Network. Retrieved August 13, 2014.
  8. ↑ Hornady ballistics charts
  9. ↑ http://demigodllc.com/articles/6.5-shootout-260-6.5x47-6.5-creedmoor/ Demigod short action 6.5mm comparison article
  10. ↑ D'Alessandro, Joe. "The Ruger M77 Hawkeye - 6.5 Creedmoor Part II Handloading the 6.5 Creedmoor for the M77". RealGuns.com. Retrieved August 22, 2015.
  11. ↑ http://www.chuckhawks.com/mpbr_hunting.htm maximum point blank range
  12. ↑ Wakeman, Randy (2012). "Savage Model 11 Lightweight Hunter 6.5mm Creedmoor Rifle". ChuckHawks.com. Retrieved August 22, 2015.
  13. ↑ 6.5mm Creedmoor - .260 Done Right? page 4
  14. 1 2 http://bulletin.accurateshooter.com/2016/11/lapua-now-offers-6-5-creedmoor-cartridge-brass/
  15. ↑ http://bulletin.accurateshooter.com/2017/02/lapua-6-5-creedmoor-brass-has-arrived-at-graf-sons/
  16. 1 2 http://saami.org/specifications_and_information/publications/download/Z299-4_ANSI-SAAMI_CFR.pdf#page=48
  17. ↑ http://precisionrifleblog.com/2015/10/12/best-rifle-caliber/
  18. ↑ http://www.accurateshooter.com/featured/65x47/
  19. ↑ http://www.shootingtimes.com/ammo/ammunition_st_creedmoor_201008/
  20. ↑ http://www.rifleshootermag.com/ammo/ammunition_rs_pedigreed_200811/
  21. ↑ http://bulletin.accurateshooter.com/2008/09/hornady-tempers-load-on-65-creedmoor-ammunition/
  22. ↑ http://forum.accurateshooter.com/threads/6-5-creedmoor-lapua-brass.3908200/page-3
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