Question What is the purpose of the hole in the exposed hammer of a hand gun?
Answer Steve,
Hammers don't need much mass - the spring is what really causes the ignition. Holes in hammers are largely cosmetic. Some people will try to tell you that the lower mass of a "holed hammer" will speed locktime. This may be an issue on a precision rifle shooting at 1000 meters. It's irrelevant on a handgun.