THE ANATOMY OF A RIFLE CARTIRDGE

Each component has a critical part to play in the firing of the cartridge, and as a hand loader, you have the opportunity to customise these components to maximise the performance of the ammunition you produce.

THE PRIMER

This is a small explosive cap that’s pressed with an interference fit into the case head. It’s struck by the firing pin, which provides ignition for the gunpowder (propellant) in the case.

Primers come in two sizes: small and large. The majority of hunting calibres use large, with some exceptions. Both sizes come in standard and magnum options for larger case capacity calibres, the difference being that the magnum primer burns 15-30% hotter, providing a more consistent and uniform ignition of the powder charge. You’ll also see ‘premium’ or ‘match’ primers and ‘standard’ primers. The main difference between them is the premium and match are manufactured under more stringent quality control.

Note: When handling primers, try to avoid touching them with your fingers. The oils from your hands can cause them to misfire.

When priming cases, always wear safety glasses. Don’t forget – the primer is a small explosive