The entire skin of a commercial aircraft is constructed pretty much in an identical manner. There simply are no "Weak spots" where a bullet size hole will cause a wider failure.

I think part of the problem with peoples perception of this is that they think the "high pressure" air, ripping out of the hole contains massive amounts of energy, and will tear the hull or window and make a larger hole. There's simply not enough energy released for this to happen. A typical aircraft hull pressure differential at 30,000-40,000 ft is 7-8 PSI. Fill up an air compressor with 8 psi, and open the pressure relief or the drain valve, and tell me if theres enough energy there to damage anything.

I seriously would challenge anyone to find a police department using FMJ (Non hollow point) ammo. They may exist, but they would be extremely rare. Not really an issue anyway.

By the by, what the h*ll is a dum-dum?