Originally Posted By: Jack Roberts"It's a bad idea. The vibration of the tumbler can break down the powder into a finer mix, and it will ignite differently, increasing chamber pressures."
This is just an old wives tale. If it were true ammo that had been shipped by truck or airplane would be no good.
Jack
OH MY GOD!!!!!!!!!!!
AN OLD WIVES TALE????
First of all, put your hand on your tumbler when it's running and let me know how much it feels like a truck, or an airplane.
Second, I quote this straight from my Sierra reloading manual:
Regardless of the method used, handloaders should never tumble loaded ammunition. Doing so may cause a deterioration of the powder's deterrent coating, or, in extreme cases, may damage the powder itself. Either situation would alter the burning rate, possible raising pressures to dangerous levels.
But then, what do they know?