If your 686 is a -5 with the floating firing pin (frame mounted instead of hammer mounted) the other main feature of the C&S pin, beside being longer, is the slot that limits the fore and aft travel is also longer. This does assist in more positive ignition. The only down side is you must have snap caps in the chamber when dry firing. Otherwise you could damage the gun. No knowkedge of Apex, but I'm guessing it's the same design as C&S.

Bryan78 kind of beat me to it.