Gunsmithing M9 Safety issues

Re: M9 Safety issues

check the safety plunger spring on the left side of the safety/decocker. also the hammer drop plunger spring on the right side of the safety/decocker. Since you have to take the slide all the way apart I would go ahead and replace the, firing pin block spring, and the firing pin and firing pin spring. I forgot to add, replace the extractor and extractor spring as well.
 
Re: M9 Safety issues

I can't comment on he cause of your problem, but I don't see how this is a major safety issue.

I have a Beretta 92G which is designed to do just what you said. As I chamber a round the "safety" serves only as a de-cocker and returns to the fire position as soon as I finish de-cocking the pistol. It will not stay "on Safe" no matter what. I personally like that system better that the Safety as found on the 92F or FS which in my experience is awkward and can be inadvertently be activated causing the gun not to fire. The Beretta "G" models eliminate this possibility of this. Besides that it is the same way that a Sig handgun works, there is not a "Safety" only a De-cocker and a first shot double action pull.

JMC