European alternative to .50 BMG. Developed to comply with French restrictions on military-caliber ammunition. Slightly different dimensions avoid legal issues.
Type: Rifle
Introduced: 2003, France/United States
Parent case: .50 BMG
Standardization: Proprietary
Bullet diameter: 0.51" (12.95 mm)
Case length: 3.898" (99 mm)
Overall length: 5.78" (146.8 mm)
Max pressure: 55,000 PSI
Rim type: Rimless
Primer: .50 BMG primer
Typical twist rate: 1:15
Muzzle velocity: 2800–3000 fps
Muzzle energy: 13000–15000 ft-lbs
Effective range: 2500 yd
Common bullet weights: 750, 800 gr
Primary use: Military, Target
Production status: Limited
Also known as: .510 DTC · 12.95x99mm
History: Developed in 2003 to circumvent European regulations prohibiting civilian ownership of military-caliber ammunition. By changing dimensions slightly from .50 BMG, it became legally distinct. Popular in France and other European countries with .50 BMG restrictions. Ballistically very similar to .50 BMG. Allows European shooters and manufacturers to work with .50-caliber-class cartridges legally.
Notable firearms: PGM Hecate II, Accuracy International AX50 ELR, European anti-material rifles
Similar cartridges: .50 BMG, .416 Barrett, 12.7x108mm Soviet