I recently purchased a used Clark Custom K-frame model 14-4 PPC revolver with a Wichita Rib Sight. Can anyone please tell me anything about the Wichita sights on adjustments and specifically what the 4 allen screws numbered 1-4 are for above the thumb wheel? Thanks as any info will be truly appreciated!

Those are presets....for making yardine (typically 7, 15, 25 and 50yds) adjustments to the sight without a screwdriver.

Here's some company info:

History

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Ret. LE, FA Instr, S&W Armorer

I have Wichita ribs on my PPC guns. For shooting PPC, my settings are: #1- dead on at 7 & 15 yards. #2- neck hold at 25 yards. #3- neck hold at 50 yards. #4 neck hold at 25 yards on B34 reduced size target.

If you have the newer style with the front sight elevation adjustment, you can use that to move all the settings as a group without doing each one on the rear sight individually.