Good idea, Standing Wolf. Maybe one of the "steamer" type vacuum cleaners. They spray cleaning fluid, or water in this case, on the carpet and then you sweep it up. The powder will never have a chance to pass near the motor.
If at all possible, WhoKnowsWho, see if you can find a reloading area away from a carpet. It can cause all sorts of problems in the future, spilled primers are a bear to find in a carpet, spilled powder as you mentioned, static electricity can really make scales, both electronic and beam balances, do funny things not to mention the sparks it can create.