The Thumbing draw is a one-handed draw, where the thumb of the gun-hand cocks the hammer while the gun is being drawn from the holster. When the gun comes in line with the target the index finger pulls the trigger to fire the gun.
There are a couple of main styles used in thumbing. One is often called "ball thumbing", and starts with the thumb positioned above the hammer, parallel with it. The thumb comes straight down on the hammer and cocks it using the main pad (ball) of the thumb.
The second style starts with the thumb positioned above the hammer and across it. When drawing the gun the thumb comes down across the hammer, often catching it around the first joint of the thumb. This is sometimes referred to as a more "natural" draw because the thumb naturally cocks the hammer as the hand closes around the gun. This style is often called "pinch" or "web" thumbing.
Waiting for the light
- The gun hand is close to the gun prior to the light signal. This shooter utilizes the "pinch" method of thumbing. You might notice that the thumb is positioned to come straight down across the hammer while grabbing the gun during the draw. You'll notice that the index finger is positioned well away from the trigger to prevent firing the gun until it comes in line with the target.
Starting the draw
- The thumb has come down across the hammer and is in the final stages of bringing it to full-cock. The rest of the fingers are closing around the gun to start the draw.
Bringing the gun in-line
- The gun is now fully-cocked and ready to fire. The wrist of the gun hand starts to pivot to bring the gun in-line with the target. The index finger is entering the trigger guard in preparation of pulling the trigger.
Firing
- The trigger has been pulled, the hammer has fallen, detonating the shell and firing grains of black powder at the balloon target. As the balloon breaks it releases a micro-switch causing the clock to stop.