A buddy made something similar once. He cut the bottom out of a 2 gallon bucket, then glued an embroidery hoop in the bottom that contained the screen. Bouncing up and down on the screen is the most effective movement. I use a bucket with insect screen on the bottom to clean seeds.
Perfect size for the drumming rig. If you go bigger bucket you might need bigger mallet headed drumsticks both with a larger head and larger length. But those are 15" long and the head is around 1" diameter (I didn’t measure) and as long as you disinfect the rubber mallet heads you’re good to go. But yeah, those drum sticks totally work
Not sure if this would be ideal or overkill but we make a bucket sieve that is cheap(ish) and may help.
It wraps over a standard 5-gallon bucket and vibrates at different frequencies. We made it for wet sieving but don’t see why it can’t help on dry. We have electric and pneumatic. Suppose it’s better than beating your drum, or not. Pun intended.