It sounds like he wants to train at home, not at a range. Your best bet for this is what Taliv described. You want to get good at fixing that problem fast, but don't neglect good tactics. Remember the difference between an immediate action drill and a remedial action drill. Sling the rifle and either get to cover or draw your sidearm, as the situation allows. Once the threat is gone, figure out why your boom stick won't boom.
For at a range, mix up a magazine of dummy rounds, live rounds, and empty cases. You'll get plenty of opportunity to clear jams, and to switch magazines.
Mike