Cartridge comparison
12.7x81mmSR Vickers vs .55 Boys
12.7x81mmSR Vickers and .55 Boys are both in the reference; see the full spec comparison below.
Side by side
| 12.7x81mmSR Vickers | .55 Boys | |
|---|---|---|
| Type | Rifle | Rifle |
| Introduced | 1925 | 1937 |
| Bullet diameter | 0.5138″ | 0.565″ |
| Case length | 3.1969″ | 3.85″ |
| Max pressure | 45,000 psi | 68,000 psi |
| Recoil | 60–80 ft·lb | 70–90 ft·lb |
| Effective range | 800 yd | 300 yd |
Highlighted cells hold the clear edge where both sides have a number. Every figure is a range maximum from the reference; typical loads run lower.
Case profiles, to scale
Drawn to the same scale, so the proportions are true. Physical size varies with your screen.