Is that a Model 21 converted to 10 MM? Details about the adjustable sights? You can drop a Model 20 conversion barrel in a Model 21. Nothing to it. OK IIRC that does not work in reverse though. Model 20 to 21? IIRC the .45 barrel will not fit in the 10mm slide. A G21 slide and barrel will fit on the G20 frame but at that point might as well have a complete G21 pistol.
Every normal man must be tempted, at times, to spit on his hands, hoist the black flag, and begin slitting throats.
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