The 410 Gauge (410 Bore) shotgun cartridge is the only shotshell named by caliber (diameter) rather than the old "gauge" designation of round balls to the pound. Introduced in the U.S. in the early 1900s the 410 Gauge is the smallest shotshell in common use, offered in 2.5-inch loads with a 1/2-ounce payload and 3-inch loads with 3/4-ounce payloads. Most modern shotguns are chambered for 3-inch shells, but the longer shells cannot be used in guns with 2.5-inch chambers. 410 Gauge is a standard event in formal American Skeet competition. Because of its light recoil the 410 Gauge is often chosen as a "starter" shotgun for youngsters, but it is not an ideal choice; the light payload sharply limits range, effectiveness, and hitting ability, frustrating the efforts of generations of youngsters--and 410 slug loads are very marginal for deer. In the right hands at close range the 410 gauge is effective on upland game, but at its best it is a choice for experienced expert shotgunners.
