
| Type | API |
|---|---|
| Projectile | steel, aluminum windscreen, black, red band, 1 copper driving band Projectile Markings: (white ink) 20MM API MN20A1 NWM-?-4 (stamped) MN 20 A1 DN - 2 - 4 - 68 |
| Case | brass, choke crimp Markings: (black ink) 20 MM M103 NWM-1-8-72 |
| Primer | electric (fired), flat, brass, ring crimp, red annulus |
| Headstamp | [none] |
| Notes | Projectile has been pulled, powder has been replaced with a ball bearing. |