Annihilator
Emissary
Nice article on the sniper rifles and shotguns of WWI, good read.
www.americanrifleman.org
An Official Journal Of The NRA | Over There: Sniper Rifles and Shotguns in World War I
Watch this American Rifleman Television video segment 'Over There! Part 8' to learn about the role of American snipers in World War I, the use of "trench gun" shotguns and the end of World War I.