Keep in mind that lead dust is also produced by the pellet proceeding down the barrel. That's one of the reasons I've gone over to lead-free pellets in most cases. They're more expensive, but I've found that when firing them into rubber mulch at relatively low power (as you might when indoors), many of the lead free pellets can be recovered and reused, since they don't typically deform, unless they hit, or are hit by, other pellets. Just a thought.