First let’s take a look at the assembled action for some perspective:
The mainspring serves two functions. Through the Hammer Spring Lever, it powers the hammer to fire the rounds, and through the Return Lever it resets the trigger and all the internal mechanisms. This is not different conceptually than the single spring used in a traditional “V”-spring Colt, or the single coil spring used in the Ruger Redhawk – though it is substantially more complicated than either of those.
The Hammer Spring Lever and the Return Lever share a common pivot pin, and the mainspring is held under tension between them. The mainspring forces the Hammer Spring Lever to rotate counter-clockwise, while it simultaneously applies force to the Return Lever in a clockwise direction. Taking out the unnecessary parts for clarity, we can get a better look at how the Return Lever functions:
The Return Lever’s force is clockwise, and as a result is always trying to pull the Lifting Lever (what everyone else calls a ‘hand’) downward. The Lifting Lever has a hook shape at its bottom end, which curls around a projection on the underside of the Return Lever. The Interlink Lever has a projection on its left end, which also has a peg on the underside. This peg fits into a hole in the Lifting Lever.
The Cylinder Stop Lever projects up through the frame and engages the notches on the cylinder, locking it in place so that the chamber is aligned with the barrel. As the trigger is operated, the Interlink Lever rotates clockwise; a rounded projection on its right side fits into a semi-circular recess in the Cylinder Stop Lever. As the projection moves downward it pulls the Cylinder Stop Lever with it, releasing the cylinder so that it can turn.
The Interlink Lever, connected to the Lifting Lever through the hidden pin on its backside, also transmits its clockwise rotation to the Lifting Lever, causing it to rise. The Lifting Lever has a finger that projects through the frame (in a more-or-less conventional fashion), engaging the unlocked cylinder and rotating it.
As the trigger completes its travel and the gun has fired, the shooter relaxes pressure on the trigger. The Return Lever – now under a fully tensioned mainspring – rotates clockwise, the projection on its right side engaging the large “C” on the Lifting Lever and pulling it back down to the rest position. The Lifting Lever pushes the Interlink Lever downward (counter-clockwise), which in turn pushes the trigger back to its home position.
If your head isn’t swimming yet you may have a future as a Rhino gunsmith!
The mechanism is full of friction points, and the only way this guns works as well as it does is because of how those friction points are handled. In the final installment of this series, we’ll look at what makes all this complication possible: the Rhino’s unique roller bearing system.
Tune in next Wednesday!
-=[ Grant ]=-