Your headspace appears to be within allowable tolerances.

Lack of protrusion could be an issue. Normally, the nose protrudes approx. .040" - .045" beyond the breechface. (a dime is .050") Tolerances allowed among the various parts involved can sometimes cause protrusion to be a bit shorter or longer. Another possibility would be damage to the hammer nose, the hammer nose bushing, dirt/debris or damage in the hammer cavity in the frame.....or debris or dirt behind the extractor. (and there are others)

__________________
Ret. LE, FA Instr, S&W Armorer