Deliver dependable ignition. Non-corrosive, non-mercuric. Consistent in size and quality. Maintain stability in extremes of temperature and humidity Winchester® non-corrosive, all weather primers deliver fast, dependable ignition under any shooting condition. In Winchester testing labs, primers are constantly and rigorously tested for consistency and sensitivity at temperatures and conditions far beyond the range of normal usage. Winchester pistol primers maintain stability in extremes of temperature and humidity in both loaded ammunition or stored in boxes on the shelf.