No doubt you have heard of the bungled hit on Alexeev in Moscow and as I have commented on such matters before I would like to deplore the amateurish nature of it, commendable youthful exuberance and enthusiasm required to get in the position notwithstanding. Place your barrel on or very close to the base of the back of skull/neck, and fire once. Your target deserves professionalism, free of undue suffering and certainly not this 'sloppy Luigi' style.