Engineering:6.5×25 mm CBJ

6.5×25mm CBJ
Place of origin	Sweden
Production history
Manufacturer	CBJ Tech AB
Variants	CBJ CBJ ST (spoon tip) CBJ HET (high energy transfer) CBJ subsonic AP CBJ TRP (training reduced penetration) CBJ frangible CBJ Blank CBJ drill
Specifications
Parent case	9×19mm Parabellum
Case type	Rimless, bottleneck
Bullet diameter	0.157 in (4.0 mm)
Overall length	1.169 in (29.7 mm)
Primer type	Large pistol

The 6.5×25mm CBJ is a firearm cartridge designed by CBJ Tech AB, a Swedish weapon development company based in Kungsbacka, for its CBJ-MS submachine gun/personal defence weapon.

Description

Named after CBJ Tech AB's founder and president Carl Bertie Johansson, the 6.5×25mm CBJ has the same functional dimensions as the 9×19mm Parabellum and was designed to produce the same recoil and pressures to allow most 9 mm caliber weapons to be converted to 6.5×25mm CBJ with a simple barrel change. Also, because the 6.5×25mm CBJ has the same overall dimensions as the 9×19mm Parabellum, it can be used in the same magazines. The primary loading of the standard ball round fires a saboted 2 g (31 gr), 4 mm diameter tungsten kinetic penetrator, weighing a total of 2.5 g (39 gr) with the sabot. It has a muzzle velocity of 730 m/s (2,400 ft/s) from a 120 mm (4.7 in) barrel with a muzzle energy of 533 J (393 ft⋅lb). From a 300 mm (12 in) barrel, it has a muzzle velocity of 900 m/s (3,000 ft/s) with a muzzle energy of 810 J (600 ft⋅lb), and has good armor penetration out to 400 m (440 yd). The standard saboted tungsten ball, when fired from a 300 mm length barrel, can pierce 9 mm (0.35 in) of armor plate and leave a 6 mm diameter entry hole. Against the same plate, both 5.56×45mm NATO SS109 and 7.62×51mm NATO M80 failed to penetrate. From a 300 mm barrel, the tungsten saboted round has the same trajectory as a 5.56 NATO from an M4 carbine and a velocity of 578 m/s (1,900 ft/s) at 300 m (328 yd), which will penetrate CRISAT armor. The 6.5×25mm CBJ bullets are slower and heavier than both the FN 5.7×28mm and HK 4.6×30mm.

There are several other 6.5×25mm CBJ bullets other than the sabot in full-caliber. Military rounds include a "spoon-tip" loading that increases the chance of the bullet to yaw on impact, and a cheap training version with a different core material. Police rounds include a 2.5 g (39 gr) high-energy-transfer round that can penetrate CRISAT armor at up to 50 meters, and a frangible round for training and situations requiring minimal barrier penetration. A subsonic armor-piercing round weighs 8 g (120 gr) for use with a suppressor.

See also

• List of cartridges by caliber
• List of rifle cartridges
• 5.7×28mm
• 4.6×30mm
• 6 mm caliber

External links

• A new weapon system from Sweden