You need to check with police because what if it's a stolen or firearm used in a crime? Call in and have the weapons serial number checked out.
Keep it and say nothing...
I happened upon a weapon. What should I do?
Keep it and say nothing?
Turn it into the police?
The idiot that lost it shouldn't have it.
You don't know that the owner doesn't deserve his property back. The one thing you do know, it's not yours.
Just so you know. This is no joke, I did find this and it was loaded in a public place. I will be taking it to the police.