I didn't think about that. That's really cool. Was this part of the design or was it an unintended benefit?
Howdy
Probably an unexpected benefit.
This is my old Uberti replica 1851 Colt Navy Cap & Ball revolver. Although it is historically incorrect in several details; the 1851 Navy was never chambered in 44 caliber, and it never had a brass frame, notice the shape of the grip. That is correct for the 1851 36 caliber Colt Navy.
When Colt brought out the 44 caliber 1860 Army Colt, the grip was about 1/4" longer than the grip of the 1851 Navy. The revolver at the top of this photo is a Pietta replica of the 44 caliber Cap & Ball Colt Army. Although the grip shape is a little bit incorrect, you can see how much longer it is than the earlier 1851 Colt Navy.
When William Mason, designed the Colt Single Action Army cartridge revolver, he chose to revert to the grip shape of the 1851 Navy, rather than the longer grip of the 1860 Colt. The revolver at the bottom of this photo is a 2nd Generation Colt SAA, to show the different grip shape.
The SAA was of course considerably more powerful than any of its Cap & Ball predecessors, firing a 250 grain bullet with a charge of 40 grains of Black Powder. This caused it to develop considerably more recoil than the earlier Cap & Ball designs.
When I first started shooting Cowboy Action, I remember one of my friends would wrap a band aide around the knuckle of his middle finger before shooting his 45 Colt revolvers. He was shooting relatively mild loads, but cramming his entire hand onto the grip resulted in the knuckle of his middle finger being in direct contact with the rear of the trigger guard. So every time he fired, the trigger guard was whacking the knuckle of his middle finger. The band aide around the knuckle was his solution.
It was about that time that I realized if I curled my pinky below the grip, that would lower my grasp on the grip of the revolver, and open up a space about 1/4" between the rear of the trigger guard and the knuckle of my middle finger. The 1/4" of space prevented the trigger guard from whacking my knuckle.
I learned not to hold the revolver in a vice like grip, instead I allow the grip to rotate slightly in my hand in recoil. The pinky is still below the grip, but I can control my stout Black Powder 45 Colt loads just fine this way, and my knuckle never gets whacked in recoil. With the muzzle up in recoil, that brings the hammer spur a bit closer to my thumb, which makes it easier to cock the hammer as I lower the revolver for a follow up shot. (Yes, I always fire a single action revolver with just one hand, always cocking the hammer with the thumb of my right hand. None of that two handed grip stuff for me with a Colt.)
So whether Mason reverted to the Navy style grip because he knew it would rotate better in the hand, he probably did know that, or whether it is an unintended benefit, it certainly works for me. With the muzzle rising during recoil, some of the energy of recoil is dissipated and the pistol tends to not smack the hand so hard in recoil as when the revolver is held with a vice like grip.