Primer (firearms)

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In firearms and artillery, the primer () is the chemical and/or device responsible for initiating the propellant combustion that will propel the projectiles out of the gun barrel. In early black powder guns such as muzzleloaders, the primer was essentially the same chemical as the main propellant (albeit usually in a finer-powdered form), but poured into an external flash pan, where it could be ignited by an ignition source such as a slow match or a flintlock, though some muzzleloaders have primers like cap gun caps. This external powder was connected through a small opening at the rear of the gun barrel that led to the main charge within the barrel. As gunpowder will not burn when wet, this made it difficult (or even impossible) to fire these types of weapons in rainy or humid conditions. Modern primers, by contrast, are more specialized and distinct from the main propellant they are designed to ignite. They are of two types, those using shock-sensitive chemicals, and those reliant on...

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