20-gauge shotgun

20-gauge/20-bore
Three 234" 20-gauge shells (right) loaded with #712 birdshot
TypeShotgun
Place of originUnited Kingdom
Production history
ManufacturerVarious
Variants212" (63.5 mm)
234" (70 mm)
3" (76.2 mm)
Specifications
Case typeRimmed, straight
Bullet diameter.615 in (15.6 mm)
Shoulder diameter.684 in (17.4 mm)
Base diameter.697 in (17.7 mm)
Rim diameter.766 in (19.5 mm)
Rim thickness.0484 in (1.23 mm)
Case length2.76 in (70 mm)
Primer typeShotshell primer
Maximum pressure12,000 psi (83 MPa)
Ballistic performance
Bullet mass/type Velocity Energy
273.438 gr (18 g) 58 oz. Remington Slugger 234" Slug 1,800 ft/s (550 m/s) 1,967 ft⋅lbf (2,667 J)
273.438 gr (18 g) 58 oz. Remington Slugger 234" Slug 1,580 ft/s (480 m/s) 1,513 ft⋅lbf (2,051 J)
468 gr (30 g) Federal 234" 118 oz. #3 Buckshot 1,200 ft/s (370 m/s) 1,496 ft⋅lbf (2,028 J)
546.875 gr (35 g) 114 oz. Fiocchi 3" #5 Shot 1,200 ft/s (370 m/s) 1,748 ft⋅lbf (2,370 J)
382.812 gr (25 g) 78 oz. Winchester 234" #712 Shot 1,200 ft/s (370 m/s) 1,224 ft⋅lbf (1,660 J)

A 20-gauge shotgun, also known as 20 bore or 20 gauge, is a type of smoothbore shotgun. Twenty-gauge shotguns have a bore diameter of .615 in (15.6 mm), while a 12-gauge shotgun has a bore diameter of .729 in (18.5 mm). Twelve-gauge and 20-gauge shotguns are the most popular gauges in the United States, where ownership of firearms is common. The 20-gauge is popular among upland game hunters, target shooters, and skeet shooters in many areas of the world.