Backyard Dig Yields Live Cannonball In New Jersey By Newser Editors and Wire Services Posted Sep 1, 2015 10:53 AM CDT 10 comments Comments Stock image. (Shutterstock) (Newser) – The Atlantic City bomb squad was dispatched to a southern New Jersey home over the weekend after a man dug up a live cannonball in his backyard. Police say the Lower Township man was digging behind his West Bates Avenue home when he discovered the explosive Saturday. Police say the brass-capped cannonball was approximately 5 inches in circumference and was stamped "4k, 85mm." Officials say the bomb squad took an X-ray of the device and determined it was fully functional. The cannonball was later detonated in an unpopulated area. Police say the discovery is not unusual for this part of the state, but residents are advised to never touch or move any found artillery shells. Originally fired as solid projectiles, cannonballs developed over time to include fuses and explosive materials.