re: Have a pistol missing, advice needed

I would do nothing and definitely not report it to the police. There is no record of you owning it so you have nothing to worry about if it is ever used in a crime; can’t be traced back to you.

Never volunteer information you don’t need to give.

In the future, lock up what you don’t want stolen or hover over the contractors.

Bad situation all around.

Still it was not your fault the pistol was stolen. There being no paper trail to you gives you the option of not reporting it stolen and even if you do report it, the police might investigate the GC's employees and find the gun but if you can't prove it is yours you may not get it back anyway. On the other hand if the gun is used in a crime and the guy who took it tells the cops where it came from they may ask you why you didn't report it stolen. I say report it, play it safe.

The contractor was finished and gone.

The theft report happened afterward and then the discovery of the items, and then an embarrassing apology, and then gracious forgiveness.