Because of the unique nature of trench warfare during WWI, new and innovative firearms were developed to meet the needs of the troops in the trench. Thus the "Trench Gun" was born. As everyone knows, a shotgun at close range loaded with buckshot is a devastating weapon. It was proved during the Philippine campaigns, the US Army purchased several hundred John Browning designed Winchester 1897 riot shotguns to use VS the Moro Tribesman. General Pershing and other high ranking officers having witnessed the effectiveness of the Winchester 1897 shotgun in the Philippines, they selected the Winchester 1897 was their first pick.
The Winchester 1897 was slightly Re-designed to accommodate trench warfare, Including a bayonet mount, and a barrel shroud.
This new use of shotguns in trench warfare had the Germans so riled and shook up the issued a protest against the US Government, saying they would execute any soldier found carrying a shotgun or shotshells (rather stupid since they were using poison gas). The US responded by strongly refusing to stop using the shotguns, and that there would be serious consequences if the Germans carried out their threat of executing Allied soldiers.
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