Iver Johnson MF20 Semi-Automatic AR Style Shotgun 20 Gauge 3" Chamber 20" Barrel (2)-5Rd Magazines Tactical Synthetic Stock Black Finish

The 20-gauge follows the 12-gauge as America's second-most popular shotgun gauge. And, with modern shotshells, continues to gain ground. The 20-gauge has a bore diameter of .615-inch, with modern shells in either 2 3/4 "standard" or 3-inch "magnum" length. Most modern shotguns are chambered to handle both. Payloads vary from light-recoiling 5/8-ounce loads all the way to heavy turkey loads carrying 1 5/16 ounces of shot. Standard 2 3/4" loads for targets and upland birds are normally 7/8 or one ounce. At its very best the 20-gauge does not have the capability of a 12-gauge...but with modern shot, wad columns, and chokes it doesn't give up much, and it can be built into a much lighter shotgun developing less recoil. Virtually all manufacturers offer 20-gauge guns, and they are available in all action types and for virtually all shotgunning sports. The 20-gauge joins the 12, 28, and .410 as one of four events in skeet competition, and is becoming increasingly popular for sporting clays. — Craig Boddington