That might work for me. I might do it further back by the mane though so they wouldn't be prepared for a boom and get a stick instead. (that's what I do before giving an injection) I want it to be something that they only get when a loud noise about to happen.
Talk to it and tell it what is going to happen. You will be surprised what they understand from us. It may sound funny but it is better than sitting on the ground with a busted rear end. : )