Step 1Combine cumin, chili powder, salt and pepper in small dish. Rub spice mix into drumsticks. Place in baking dish lined with foil.
Step 2Roast drumsticks, uncovered, at 375 degrees, turning them every 15 minutes, until lightly browned and juices run clear when pierced with tip of sharp paring knife, about 55 minutes. Generously brush 1/4 cup barbecue sauce over drumsticks. Roast 10 minutes more.
Step 3Remove meat from bones, discarding tendons and skin. Put meat in bowl. Heat remaining barbecue sauce then toss with meat. Divide evenly on buns; serve warm.