Howdy
Nothing New Under the Sun Department:
I came across a big X frame Smith with the ball detent system mounted in the crane a couple of years ago.
This is vaguely reminiscent (not the same) as the yoke lock in the S&W 44 Hand Ejector, 1st Model, commonly referred to as the Triple Lock. This nickel plated Triple Lock shipped in 1915.
The Triple Lock was the first large caliber revolver that S&W made with a swing out cylinder. It was first cataloged in 1908, and it was chambered for the brand new 44 Special cartridge. The Triple Lock was unique in that in addition to latching the cylinder in place at the front and rear of the extractor rod, there was a third latch built into the extractor rod shroud and the yoke. The Triple Lock was also the first Smith to have an extractor shroud, the shroud was there to house the third latch mechanism.
The plunger portion of the third latch was a U shaped part. It was held in place in the shroud by two pins. There was also a small 'button', part of the shroud that protruded slightly forward of the shroud.
Here is a view of the business portion of the plunger. With the cylinder open the spring at the front of the plunger has extended both the upper and lower portions of the plunger out. Notice there is a bevel cut onto the lower portion of the plunger.
A hardened insert was fitted into the yoke. A ramp and a deep hole were machined into the insert.
The Triple Lock had a thumb piece mounted onto the side of the frame just like any other swing out cylinder Smith. Pushing the thumb piece forward disengaged all three latches, just like any other Smith. Since the yoke plunger was a single U shaped piece, when the extractor rod pushed the upper portion of the plunger forward, the bottom portion came along for the ride, disengaging the yoke lock.
When the cylinder closed, the beveled portion of the plunger rode up the ramp portion of the insert, pushing the upper portion back too. As the plunger cleared the hole, it dropped into the hole, and the upper portion of the plunger came along for the ride.
Most experts agree the third latch of the Triple Lock was completely unnecessary, S&W was simply displaying their prowess at making complicated, detailed assemblies. Triple Lock production ceased in 1915, and Smith and Wesson never built another revolver with a third latch until recently with the ball detent system, which is obviously much less expensive to build than the third latch of the Triple Lock.
When the 44 Hand Ejector 2nd Model appeared in 1915, the third latch had been eliminated, along with the extractor rod shroud. The Triple Lock sold for $21, the 2nd Model without the third latch sold for $19, a significant cost savings at the time.