You have stumbled onto a weakness that dogs have toward loud popping noises. I first found out that this works, when I would pop a paper bag. Some really have a time of it during the 4th. of July. Yes, they will respond to your caps but better than this, try popping a pellet gun without inserting a pellet. I have a Rotweiler for as a neighbor and they love to bark. I wait and when the barking goes on for too long, I just pop my pellet gun. He charges into his garage and sometimes will not come out for a couple of hours. I like the dog but sometimes it gets to be too much as he really can't help this barking.
I would think that just about any loud pop will give you the results you want and you can save you caps as well as eliminating any of souce of corrosion. ....
Be Safe !!!