Although cylinder boss on Webley Mk VI revolver serves as retaining feature, to hold cylinder attached on barrel:
It works also as deflector of powder, lead and grease debris from getting into the bore.
Since Mk VI was initially designed as a military black powder firearm, designers took extra measures in case some debris and dirt get into cylinder central hole. To prevent them from clogging revolver, they added spiral groove on cylinder axis, attached to barrel:
It works also as deflector of powder, lead and grease debris from getting into the bore.
Since Mk VI was initially designed as a military black powder firearm, designers took extra measures in case some debris and dirt get into cylinder central hole. To prevent them from clogging revolver, they added spiral groove on cylinder axis, attached to barrel: