7.62x51 CBJWith subcaliber technology
The subcaliber technology is scalable and is now being utilized on other common cartridges like the 7.62×51 Nato and the new 300 Blackout. These rounds have superior armor piercing capability and accuracy, making them suitable for both sniping at long ranges and engaging hard targets like APC´s or personnel with advanced body armor.
The subcaliber technology is not new. Similar products, like the SLAP, are already on the market. The problem with these is that they cannot be fed through an automatic cycling weapon without feeding problems, due to the exposed tip of the core projectile.
CBJ Tech AB´s solution is far superior to the existing products both regarding functionality and performance. The core projectile is completely encapsulated by the sabot, which has an outer geometry similar to FMJ projectiles. This ensures that the feeding works properly in automatic cycling weapons, and provides better support for the core projectile during the acceleration through the barrel. The metal gas check ensures that rotation is transferred to the core projectile through a pattern at the rear end of the core projectile without rotational slip. This gives the ammunition superior accuracy, even at high or especially at low temperatures. The development of the 7.62×51 CBJ is in its final phase and the results so far are remarkable.
Cartridges from left to right: 7.62×51 Nato FMJ, 7.62×51 SLAP and 7.62×51 CBJ
Key characteristics for the 7.62×51 CBJ:
- 6g tungsten core projectile inside 1g plastic sabot, 7g (109gr) together
- High muzzle velocity; V0 of 950-1015m/s depending on barrel length (18″ – 24″)
Extreme penetrating performance against hard targets, like armored vehicles and body armors
High hit probability due to low recoil and good ballistic performance – short time of flight and flat trajectory
High wounding effect due to high impact velocity
High system flexibility – possibility to combine with non subcaliber ammunition, like FMJ or Tracers.
Performance of the 7.62×51 CBJ
The charts below compares a typical standard 7.62×51 Ball round, the US M80, with the performance of the M993 AP, 7.62×51 SLAP and the CBJ projectile when shot from a 24” (610mm) barrel, which is typical for a sniper rifle or a machine gun.
The calculations are based on the following:
Published data has been used for the M80, M993 and SLAP.
V0 for the 7.62×51 CBJ has been verified during several tests.
The Ballistic Coefficient (BC G7) for the 7.62×51 CBJ is calculated with regards to the projectiles characteristics, like caliber, nose length, nose radius, nose shape, boat tail, density and overall length.
The data used in the calculations is as follows:
|7.62×51 M80||7.62×51 M993||7.62×51 SLAP||7.62×51 CBJ|
|BC (G7): 0.20||BC (G7): 0.176||BC (G7): 0.165||BC (G7): 0.274|
|M: 147gr (9.5g)||M: 126.6gr (8.2g)||M : 60gr (3.9g)||M: 93gr (6g)|
|V0: 833m/s||V0: 930m/s||V0: 1220m/s||V0: 1015m/s|
Penetrating performance of the 7.62×51 CBJ
Testing is continuously being done in order to evaluate the penetration performance of the 7.62×51 CBJ cartridge. Various armor plates have been tested with very good results as well as some types of body armor.
The first picture shows an armor plate that has been shot at 10 m range. The hardness of the plate is 300 HB and the thickness is 18mm. The left hit is from a 7.62×51 FMJ and the right hit is from a 7.62×51 CBJ.
Other tests have been bade against body armors, and the results show that the 7.62×51 CBJ is able to penetrate up to NIJ level IV. However it has not yet been determined at what range it can do this. The tests have only been conducted at 10 m range at this point.
Several tests have also been done against thinner armor plates like the one in the picture, which has been used in previous testing with the 6.5×25 CBJ APDS.
This armor plate is 8 mm thick and has a hardness of 450 HB.
The 7.62×51 CBJ is able to penetrate this plate at 920 m range, with a hitting velocity of 525 m/s.
Testing and tweaking is still being done but there is potential for great precision.