15x115 and 15x106 BRG-15 from FN with numbers
Cutaway model of 15x115 BRG-15 and four 15,5x106 BRG-15 cartridges. These cartridges were meant for the BRG-15 machine gun that was meant to replace the .50 (12,7x99) weapon and cartridge.
In the seventies of the last century it was felt that there was a great gap between the 12,7x99 and the 20x139mm weapons and cartridge. It also became clear that the existing .50 ammunition was ineffective against even lightly armoured Russian vehicles (10mm @30 degr) at distances over 300 mtrs. FN engineers started to design a weapon, not much heavier than the .50, however much more effective, although much cheaper than the 20x139 weapons and cartridges. The required effective range was 1000 mtrs. Computer calculations and simulations pointed out that 15,5 mm (.60) was a suitable calibre.
The BRG-15 machine gun was taken in use in 1981 and had as a special feature the dual feed, allowing the gunner to fast switch between two types of ammunition. The spent cases were ejected from the underside of the weapon.
Cartridge 01:
12,7x99 (.50) APIT catridge for size comparison
Cartridge 02:
The original design 15x115 (APHC) cartridge for the BRG-15 machine gun. The project was stopped after extensive testing. This, due to the fact that jacketed bullets did not function well at 1050 mtrs/sec, resulting in excessive barrel wear and loss of accuracy.
In June 1987 it was descided to redesign the 15 mm projectile and cartridge for the BRG-15. replacing it with the new designed 15x106 cartridge, which had a projectile with a driving band.
Cartridge 03/04/05/06/07
Because it was found out that jacketed projectiles do not function propperly above 1000 mtrs/sec. a projectile with a plastic driving band was designed.
A intermediate design (not in the picture) was the projectile shape as shown in cartridges 03 to 07 with the 115 mm long shellcase as shown with cartridge 02. The 115 mm long shellcase however had too little inner space to take the required amount of powder, so a new shellcase 15x106mm was designed (wider inside).
Cartridge 03: 15,5x106 T.P. (Target Practice), soft steel projectile with a plastic drivingband. The projectile colour is blue.
Cartridge 04: 15,5x106 T.P.T. (Target Practice Tracer), soft steel projectile with a tracer and a plastic drivingband. The projectile colour is blue with a red nosetip.
Cartridge 05: 15,5x106 APHC (Armour Piercing Hard Core). The projectile exists of a black aluminium body, housing the drivingband and the tungsten penetrator. A white plastic ballistic nose cap is crimped on top of the body.
Cartridge 06: 15,5x106 APDS (Armour Piercing Discarding Sabot). The projectile exists of a black aluminium driving sabot, housing the drivingband and the tungsten penetrator. A black plastic sabot, existing of four joined sabots is screwed on top of the body. Upon firing the sabots brake away, allowing the driving sabot to be blown away by the airstream. Only the tungsten penetrator will travel to the target with high speed.
Live fire tests started in 1988 and were a succes for weapon and ammunition. However , the changing relation between East and West, followed by large financial cuts in military spending had a negative effect on the project that was finally terminated in 1992. FN switchd to the design and production of small arms like the highly succesfull P90 PDW.
It is claimed that the 15x106 BRG-15 cartridge is even more powerfull than the Russian14,5 x 114 cartridge.
The armour penetration of the 15,5x106 (HVAP) cartridge is 10 mm @ 30 degr. at 1350 mtrs, exeeding the 100 mtrs requirement. Rate of fire of the BRG-15 was 220 rpm.
15x115 and 15x106 BRG-15 from FN with numbers
Cutaway model of 15x115 BRG-15 and four 15,5x106 BRG-15 cartridges. These cartridges were meant for the BRG-15 machine gun that was meant to replace the .50 (12,7x99) weapon and cartridge.
In the seventies of the last century it was felt that there was a great gap between the 12,7x99 and the 20x139mm weapons and cartridge. It also became clear that the existing .50 ammunition was ineffective against even lightly armoured Russian vehicles (10mm @30 degr) at distances over 300 mtrs. FN engineers started to design a weapon, not much heavier than the .50, however much more effective, although much cheaper than the 20x139 weapons and cartridges. The required effective range was 1000 mtrs. Computer calculations and simulations pointed out that 15,5 mm (.60) was a suitable calibre.
The BRG-15 machine gun was taken in use in 1981 and had as a special feature the dual feed, allowing the gunner to fast switch between two types of ammunition. The spent cases were ejected from the underside of the weapon.
Cartridge 01:
12,7x99 (.50) APIT catridge for size comparison
Cartridge 02:
The original design 15x115 (APHC) cartridge for the BRG-15 machine gun. The project was stopped after extensive testing. This, due to the fact that jacketed bullets did not function well at 1050 mtrs/sec, resulting in excessive barrel wear and loss of accuracy.
In June 1987 it was descided to redesign the 15 mm projectile and cartridge for the BRG-15. replacing it with the new designed 15x106 cartridge, which had a projectile with a driving band.
Cartridge 03/04/05/06/07
Because it was found out that jacketed projectiles do not function propperly above 1000 mtrs/sec. a projectile with a plastic driving band was designed.
A intermediate design (not in the picture) was the projectile shape as shown in cartridges 03 to 07 with the 115 mm long shellcase as shown with cartridge 02. The 115 mm long shellcase however had too little inner space to take the required amount of powder, so a new shellcase 15x106mm was designed (wider inside).
Cartridge 03: 15,5x106 T.P. (Target Practice), soft steel projectile with a plastic drivingband. The projectile colour is blue.
Cartridge 04: 15,5x106 T.P.T. (Target Practice Tracer), soft steel projectile with a tracer and a plastic drivingband. The projectile colour is blue with a red nosetip.
Cartridge 05: 15,5x106 APHC (Armour Piercing Hard Core). The projectile exists of a black aluminium body, housing the drivingband and the tungsten penetrator. A white plastic ballistic nose cap is crimped on top of the body.
Cartridge 06: 15,5x106 APDS (Armour Piercing Discarding Sabot). The projectile exists of a black aluminium driving sabot, housing the drivingband and the tungsten penetrator. A black plastic sabot, existing of four joined sabots is screwed on top of the body. Upon firing the sabots brake away, allowing the driving sabot to be blown away by the airstream. Only the tungsten penetrator will travel to the target with high speed.
Live fire tests started in 1988 and were a succes for weapon and ammunition. However , the changing relation between East and West, followed by large financial cuts in military spending had a negative effect on the project that was finally terminated in 1992. FN switchd to the design and production of small arms like the highly succesfull P90 PDW.
It is claimed that the 15x106 BRG-15 cartridge is even more powerfull than the Russian14,5 x 114 cartridge.
The armour penetration of the 15,5x106 (HVAP) cartridge is 10 mm @ 30 degr. at 1350 mtrs, exeeding the 100 mtrs requirement. Rate of fire of the BRG-15 was 220 rpm.