In my experience: GP100 is stronger and more durable, S&W has better trigger feel, GP is normally more accurate with more different bullet weights, GP normally has at least one load per gun that gives spectacular accuracy, GP is easier to disassemble and maintain, GP front sights are easy to change.
I should add I own two 4" stainless GP 100's (but my wife carries a S&W).
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"All my ammo is factory ammo"
I should add I own two 4" stainless GP 100's (but my wife carries a S&W).
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"All my ammo is factory ammo"