I hope you don't mind that I butt in, but on a single action
revolver that does not use a transfer bar, the hammer notches are not
foolproof, ie, they may not prevent the firing pin from contacting the
cartridge primer and firing a round if the pistol is dropped and
lands squarely on the hammer.  Only a transfer bar can prevent such
contact.  Barring that, resting the hammer on an empty chamber is much
safer.
--- WILDMAIL!/WC v4.12 
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