Used For Shotgun Shells
Shotshells are loaded with several different primers, which have a large impact on ballistics. Changing a primer brand can cause a large change in pressures and powder drop. Also, some primer combinations have not been tested. Changing a shotshell’s primer is only a good idea if you are confident that you are following a recipe to the letter. Otherwise, you may be creating a dangerous load that can hurt your target.
The primer is a metal component that ignites the propellant powder inside a cartridge. A shotgun shell’s primer has two parts, the anvil and the primer cap. Each part has a small amount of explosive, which is released when the firing pin strikes it. The resulting explosion in the cartridge case creates a stream of hot gases that ignite the propellant powder inside.
The ignition process involves a chemical reaction between the primer and the main propellant charge. In about two hundred and fifty microseconds, the combustion process begins and ignites the projectile. If the primers are too small, the projectile will only be partially ignited and may end up partway in the barrel of the gun. This dangerous condition is known as a squib load.
Cheddite 209 Shotshell Primers
Another common problem is loading a shell that is too large for the chamber of a shotgun. This will result in excessive pressure, which can damage the gun or injure the shooter. A shotgun shell should be no longer than two and a half inches in diameter.
What Primer Is Used For Shotgun Shells?
In addition to lead, shotgun shells can also be made from steel. While steel shells are cheaper than lead, they may cause damage to older shotguns and choke tubes. The metal used in steel shells is higher in pressure than lead shot. This can be problematic if your shotgun has a high-quality choke tube.
There are other types of shells that don’t contain a primer. In such cases, the primary propellant is ignited by an electric charge provided externally. Examples include the O’Dwyer VLE and Voere VEC-91. This is not to be confused with the electrically ignited internal primer.
Another type of shell is the rimfire cartridge. This shell has a thin brass case with a bulge around the back end. The rim is filled with a specialized primer. The firing pin then compresses the rim and ignites the propellant. The firing pin is then removed, which sends the fired shell into flight. The rim becomes impact-sensitive and the shell detonates, resulting in a highly accurate shot.
Prior to the 1950s, many primers were highly corrosive. The chlorate-priming mixture contained salts that remained in the barrel after firing. This combination combined with the moisture in the air caused bore corrosion. Federal engineers worked to come up with a primer that wouldn’t cause any damage.