• If you are citizen of an European Union member nation, you may not use this service unless you are at least 16 years old.

  • You already know Dokkio is an AI-powered assistant to organize & manage your digital files & messages. Very soon, Dokkio will support Outlook as well as One Drive. Check it out today!


MP 20x139mm

Page history last edited by Michael 6 years, 11 months ago

back to the Index or the Ordnance page



     This ammunition is used in the Oerlikon 20mm KAD or HS-820 in various NATO vehicles and by the US military for the M139 gun (used on the M114 and various aircraft). Ammunition types adopted by the Project are HEI and API, steel-cased with boxer primers; both types have tracer elements. Individual rounds weigh abut 0.31 kg and are 213mm long; the generic projectile weighs 119 grams.

     These will appear within the Project as:


    • loaded 20 round drum magazines:  6.3 kg

    • loaded 20 round drum magazines:  14.3 kg

    • loaded 50 round drum magazines:  34.3 kg

    • linked 100 round belt:  41.7 kg   (loaded with 3 API/2 HEI mix, start of belt is always API)

    • plastic box with linked 100 round belt:  43.1 kg


     Performance of the rounds is as follows:


    • M56A1 High Explosive Incendiary:  arming range 8 to 11 meters, burst radius 1 meter, self-destruct in 4 to 12 seconds. Explosive charge is 5.8 grams of Hexal P30 (a mix of RDX/cyclonite/hexogen and aluminum powder), with a combined blast/incendiary effect. Projectile mass 119 grams. Will penetrate 20mm of RHA steel .

      • damage 5d6+2, maximum penetration armor value 22. Blast does 3d6 damage out to 1 meter, maximum penetration armor value 9.

    • T221E3 Armor Piercing Incendiary: arming range (for the incendiary element) 8 to 11 meters. Projectile mass 110 grams. Tungsten carbide penetrator core will penetrate 50mm of RHA steel  at 100 meters, 32mm of RHA steel  at 1000 meters.

      • damage 5d6+2, maximum penetration armor value 31 at 100 m, armor value 24 at 1000 m

      • Rule of thumb if it comes up:  reduce penetration by 1 armor value from 31 for every 125 meters over 100 meters, out to 1000 meters

    • generic ball (22nd Century reload):  plain hard lead, simple smokeless powder propellant, projectile mass about 125 grams. Will penetrate 12mm of RHA steel at 200 meters, 10 millimeters at 400 meters.

      •  damage 5d6+2, maximum penetration armor value 17 at 200 m, armor value 16 at 400 m.


Other Handy Examples To Use Later


  • 7.62x51mm AP M993 - 15mm HB300 armour at 250 meters

  • 12.7x99mm AP M8 - 22mm MS plate at 0 degrees/100 meters

  • 12.7x99mm MP NM 140 - 16mm HB360 at 30 degrees/400 meters

  • 12.7x99mm SLAP Singapore - 25mm RHA at 0 degrees/1,000 meters

  • 20x139mm Rheinmetall API-T - 32mm armour at 0 degrees/1,000 meters

  • 25x137mm Oerlikon APDS-T - 26mm armour at 60 degrees/2,000 meters

  • 25x137mm Oerlikon APFSDS-T - 35mm armour at 60 degress/1,200 meters

  • 25x137mm M935A2 APFSDS-T - 42mm RHA at 60 degrees/1,000 meters

  • 30x165mm (2A42) AP-T - 18mm RHA at 60 degrees/1,000 meters

  • 30x170mm Rarden L14A3 APDS-T - 40mm RHA at 45 degrees/1,500 meters

  • 30x173mm Oerlikon SAPHEI-T - 12mm armour at 60 degrees/1,000 meters

  • 35x228mm Oerlikon APDS-T - 48mm armour at 60 degrees/1,000 meters

  • 35x228mm Oerlikon APFSDS-T - 100mm armour at 0 degrees/1,000 meters

  • 40x365mm Bofors APFSDS-T - 100mm+ (120mm?) armour at 1,500 meters

Comments (0)

You don't have permission to comment on this page.