Brazos from PK to below Whitney is awesome for drum! Bottom feeders, will take a lot of baits. Find rocks, gravel, sand and you'll find drum. We would always catch them on bycatch when I used to fish the Brazos but have fished for them on purpose elsewhere since then. Find a rapid and fish in both the slower current and the slack water. Sand bass are usually at the faster part of the rapid, fish the "slower" more downstream part of the rapid for the drum. Will bite anything from jigs you'd use for sand bass, curly tail grubs, cut shad, live minnows, worms........all that stuff. Worms work best as bait IMO, but I like to put out shad and catch both cats and drum, while casting a white jig or grub for them and catch some sandies too. Slow swim lures keeping constant bottom contact.
Look up drum article by Keith Sutton.