this is most likely a really stupid question, but ive gotta ask. i was poking around the midwayusa site, and stumbled across snap cap ammo that is advertised as being good for dryfiring, and basically sounds like something i could load in my gun, and use to practice drawing and firing, without firing a round. my question is A. can i fire my gun with them loaded in a house without causing damage to anything, and B. are the loads reusable, because 15 bucks for 5 shots, why not just buy a box of 50 rd. and get the real deal? i know this is a newb question, but i honestly know nothing about "snap cap" ammo.