Actually, back when several municipalities were trying to push the PA Game Commission into expanding the special regulations areas otherwise known as shotgun areas the Game Commission hired an outside research company to research if rifled slugs were safer than rifle and handgun bullets. They did this because some Senators and Representatives were threatening to take the issue out of the hands of the PGC and put it into the hands of the general assembly which would have been a disaster. The General Assembly was so sure of the results of the study that they paid for the thing. Well surprise of all surprises, the study showed that rifled slugs were actually more of a threat in a populated area because they have more of a tendency to ricochet than bullets. This made sense because in my law enforcement firearms training we were taught how to ricochet rifled slugs under vehicles to his an assailant on the other side that is shooting at officers. I got good at bouncing a slug off the ground into the chest of a silhouette target. The steeper the angle the slug is shot at the ground the higher it will bounce. To make a long story short, thus ended the attempt to expand the shotgun areas in PA.