All shotshells share a few common traits. The head and primer are similar in all shells. The hull and base wad are paper or plastic. The wad design and powder vary with the type of shotshell and its intended use. Shells can range in length from 1 3/4 to 3 1/2 inches and in payload weight from 3/8 ounce to 2 1/2 ounces. They are loaded with lead, steel, bismuth and tungsten alloy shot, as well as slugs and buckshot.

Constriction in a shotgun's muzzle is referred to as choke. The three most common chokes are full, modified and improved cylinder. Lead, steel, bismuth and tungsten pattern differently in each of these chokes. To determine which load provides the best pattern density and most even pellet distribution, make sure to pattern a variety of loads at different distances.

The gauge of a shotgun was first determined by a simple method that used lead balls. A gun maker would use lead balls the same diameter of the shotgun bore, and then count how many of those balls it takes to equal one pound of weight. For example, it takes 12 lead balls the size of a 12 gauge shotgun bore to weigh a pound. The only exception is the .410, which is measured in inches. Shotguns and shotgun shell should also be matched. Failure to properly match the ammunition to the firearm can cause firearm damage and/or personal injury.