The use of large caliber guns seem to be rare. I was shocked when I read Ralph Doles, the cop Joel Cacace ordered killed, was hit with a 44 by Dino Calabro, and his cousin, the other shooter was shooting a 45. Most times they seem to use 22's, 38's, and even 380's. There have been quite a few hits that were botched because of faulty weapons. The sister of Pete Chiodo survived because the silencer on the gun disintegrated when fired. I think a lot of times they don't test the guns out before doing the "work."