None myself, but I was standing 20 feet away from a guy who was opening the top cover of a 240 mounted on a Humvee. I don't know what he was doing ... and I don't think he did either ... but a small burst of 3 rounds made its way out. Thankfully the muzzle was pointed at a berm.
I paid $400 for mine ~4 years ago. Only half of the numbers match, but the stock, bore, bluing, and screw heads were in impeccable shape. If you do purchase it, they make birdcage flash hiders for M96 Swedes. You can buy them online for pretty cheap to protect the threads.
Sidenote: M96's...