5.56 x 45mm United States
Details
| Type | Proof, XM197 |
|---|---|
| Projectile | FMJ, GM, red tip, 1 knurled crimping cannelure |
| Case | brass, tin plated, red head |
| Primer | percussion, flat, brass, ring crimp, red, red annulus |
| Headstamp | R A 6 5 |
| Type | Proof, XM197 |
|---|---|
| Projectile | FMJ, GM, red tip, 1 knurled crimping cannelure |
| Case | brass, tin plated, red head |
| Primer | percussion, flat, brass, ring crimp, red, red annulus |
| Headstamp | R A 6 5 |