The Iver Johnson Trigger Cocking Single Action Revolver,Made by Iver Johnson from 1940 to 1947, the

The Iver Johnson Trigger Cocking Single Action Revolver,Made by Iver Johnson from 1940 to 1947, the Trigger Cocking Single Action Revolver was known for its strange cocking mechanism.  It was not a double action revolver, where pulling the trigger simultaneously spins the cylinder, cocks the pistol, and fires it.  Rather it was a single action revolver that was cocked with the trigger mechanism. The first pull of the trigger revolved the cylinder and cocked the hammer.  The second pull of the trigger fired the revolver.  The purpose of this type of action was for use by target shooters.  Target shooters who are competing for accuracy prefer single action revolvers because they have a lighter trigger pull and are more accurate.  However by cocking the hammer one my have to momentarily take the sights of the pistol of target.  The trigger cocking single action mechanism allowed the shooter to cock the pistol without going off target. Chambered in .22 Long Rifle, the revolver used a break open mechanism to eject empty casings for reloading. -- source link

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