I'll echo everyone else's comments. Your best bet is the Filmore in Silver Spring, especially if you're looking for nationally touring acts, but other venues will occasionally have shows too.

Out of curiousity, what metal venues are you seeing out towards Fairfax? Are you referring to Jaxx/Empire? If so, that permanently closed in 2015, and unless you count something like Jiffy Lube Live for huge summer shows way out in the Virginia Countryside, there aren't any metal venues anywhere near Fairfax.

I generally make the trek from Arlington to Silver Spring for the Filmore. Check out the lineup on their website to see if you like the bands that come through, but I'll be at the Spiritbox show in April.

Baltimore has a much bigger metal scene. Bands often play Boston/NYC/Philly/Baltimore, but skip DC entirely.