RWS (Rheinisch-Westfälische Sprengstoff) primers are regarded as some of the most consistent and highest-quality ignition components available to the modern reloader. The 5337 Large Pistol primer is engineered for absolute reliability in high-pressure and large-volume handgun cartridges.

Utilising the famous Sinoxid™ non-corrosive formulation, these RWS primers ensure that your firearm's bore and action remain protected from the erosive salts found in older primer styles, while providing a uniform flame front for consistent shot-to-shot velocities.

• Sinoxid™ Ignition: The world-renowned non-corrosive, non-mercuric priming compound ensures long-term storage stability and a clean burn that protects your barrel and sensitive firing pin components.

• Precise Sensitivity: Manufactured to exacting European tolerances, the 5337 is designed to ignite reliably even with the lighter firing pin strikes often found in tuned competition revolvers and semi-autos.

• Uniform Cup Dimensions: High-precision manufacturing ensures every primer seats perfectly and at a consistent depth, which is critical for preventing misfires and ensuring uniform internal ballistics.

• Optimised for Large Volumes: Engineered to produce a robust and sustained flash, making it highly effective at igniting large powder charges in big-bore calibres like .44 Magnum or .45 Colt.

• Rigid Quality Control: RWS utilises automated optical and mechanical checks during the punching and filling process to ensure every primer in the 100-count tray meets match-grade standards.