It costs less. The original cylinder retention system is a boss that I believe may have been machined separately and pressed in. That was followed by a integral boss that was nicely contoured around 2010, which was switched to what you have now in the 2016-17 time frame. Fewer cuts=less production time=more dollhairs.
Your newer one has the contoured integral boss, the older one has the circular boss that was part of the original SP design.The 4 inch I bought new in March 2017 and the 3 inch I bought new in 1989.Both look about the same to me
I have that exact same 101 on the bottom but with hogue grips. Very powerful and easy to pack .357 mag👍The 4 inch I bought new in March 2017 and the 3 inch I bought new in 1989.Both look about the same to me
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