5.56 x 45mm United States
Details
| Type | Marking |
|---|---|
| Projectile | Round Nose, aluminum, plastic tip, blue tip |
| Case | aluminum Markings: UTM 5.56 RH 13 |
| Primer | percussion, flat, brass |
| Headstamp | SB (in interlocked diamonds on primer) |
| Type | Marking |
|---|---|
| Projectile | Round Nose, aluminum, plastic tip, blue tip |
| Case | aluminum Markings: UTM 5.56 RH 13 |
| Primer | percussion, flat, brass |
| Headstamp | SB (in interlocked diamonds on primer) |