30 x 111mm B United Kingdom
Details
| Type | TP, MK 3z |
|---|---|
| Projectile | steel, black, 1 copper driving band Projectile Markings: (stamped) RG57 8B |
| Case | brass, choke crimp Markings: (stamped in extractor groove) J 30.MM. R.G. 57 |
| Primer | electric, flat, brass, ring crimp, red annulus |
| Headstamp | [none] |