 Unlike most modern pump @-@ action shotguns , the Winchester Model 1897 ( versions of which were type classified as the Model 97 or <unk> for short ) fired each time the action closed with the trigger depressed ( that is , it lacks a trigger <unk> ) . Coupled with its six @-@ shot capacity made it effective for close combat , such that troops referred to it as a " trench sweeper " . This characteristic allowed troops to fire the whole magazine with great speed . The Model 1897 was so effective , and feared , that the German government protested ( in vain ) to have it outlawed in combat . The Model 1897 was used in limited numbers during World War II by the United States Army and Marine Corps , although it was largely superseded by the similarly militarized version of the hammerless Model 1912 . 
