Me and dad took our handguns out side and were going to go practicing up until--

I get my wheel gun out of the jeep and noticed dad already loaded my chambers with the bullets I didn't want to waist; but when I pushed the release the wheel wouldn't open and it was getting ready to storm on us. We decided to come in when I told my dad the gun was jammed both of us couldn't open the revolver so I ended up firing all 5 rounds into a stump and then like magic it worked again, mysteriously.

What just happened and what should I do if this happens again without live ammo?