If your shotgun's serial number ends in M, N or U, then you have a 3-inch magnum shotgun and will need to use magnum ammunition to make it cycle correctly. (Be sure to double check the barrel for the proper size shells)
The magnum barrel only has one gas orifice hole in the gas chamber and a field load will not supply sufficient gas pressure to cycle the action in a magnum barrel. Field barrels, on the other hand, have two orifice holes and are designed for the the lighter 2 3/4-inch loads.
Most Model 1100 Magnum shotguns with the exception of pre-1977 Model 1100 20-gauge shotguns can be fitted with 2 3/4-inch field barrels for use with light field and target loads. You can find more information on factory replacement barrels through our online store at www.shopremingtoncountry.com.
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