5.56 x 45mm United States
Details
| Type | Proof, M197 |
|---|---|
| Projectile | FMJ, GM, 1 knurled crimping cannelure |
| Case | brass, taper crimp, tin plated |
| Primer | percussion, flat, brass, ring crimp, violet annulus |
| Headstamp | L C 6 8 |
| Type | Proof, M197 |
|---|---|
| Projectile | FMJ, GM, 1 knurled crimping cannelure |
| Case | brass, taper crimp, tin plated |
| Primer | percussion, flat, brass, ring crimp, violet annulus |
| Headstamp | L C 6 8 |