Posted here before is a sink strainer that fits in the drain of a kitchen sink. It is available at WalMart and will separate many large flake powders and shot. It pays to have several strainers and sometimes start large and work your way down small. As a final method that works for me, I take a clean (new) cylindrical container like a 5 gallon bucket dump the remaining shot and powder after straining. Hold the container parallel to the ground, twist or roll it back and forth and the shot will roll out, leaving the powder in the bottom of the bucket.