May 2008 Among the issues addressed in developing the chaser fleet was armament. As with the changes in models of deck guns - early photos showing Hotchkiss and Davis models, while the "standard" gun was to be the Poole 3"/23 caliber deck gun - there were multiple models of machine guns mounted on chasers.
In most of the photos that show deck guns mounted on stanchions on the bridge wings, a Colt machine gun is shown. However the Lewis machine gun was the superior weapon, and some photos show Lewis guns instead of the Colt.
This document, a pre-typed ordinance, material and ammunition inventory form, filled in to show inventory on subchaser SC 93 in September 1918, shows the chaser carrying two Lewis guns.