A professional who sets up and maintains in operation automatic machines that insert explosive primers in cartridge cases. Responsibilities include:

• Installs and adjusts punches, dies, and feed fingers, and regulates feeding and ejection mechanisms, using handtools and gauges.
• Frees jams and replaces worn or broken parts.
• Polishes steel punches and feed fingers to remove burrs, scratches, or adhering brass, using speed lathe and emery cloth.
• May feed plates or boards of primers into machine hoppers.
• May instruct new workers in machine operation and use of gauges.