- MK2
- 303
- Mk2-303 hybrid
- No
MK1
The boys rifle was developed first around the 50 caliber M2 round before that round was found lacking in penetration. The MK1 was calibrate for a .55 caliber or 13.5mm round. A later model would be adapted to fire the .50 round during the time of the Korean war. The MK1 was later replaced by the PIAT launcher.
The MK2 was an attempt to reduce the weight by cutting of 6 inches of barrel reducing the boys from 36 to 30 inches. This MK2 lacked sufficient power and was harder to control. The Mark2 with a tungsten round could penetrate 20 mm at 300 m more that 3 time the 23mm at 9m meters of the mk1.
Later a necked down 303 round was tested for practice and greater penetration. The results of these tests are unknown as knocking down increases the velocity of the projectile but decreases the weight of the projectile. knecking down means using the same .55 caliber round then neck it down to fit the smaller projectile of the 303. The 303 practice round came with an 8 shot magazine it is unkown if latter trial weapons had similar capacity.
MK2
303