While I was on my way back home from taking the rent check to my landlord, I stopped at the corner of Westchester & Glebe waiting for the cars in front of me to move, I glanced to my right and saw a sign that said "Paintball". I pulled over right away and even left my car double parked to go in and ask if they do paintball tank refills, he said YES!!! they charge $6+tax for a 20oz, which is WAY better than the $10+tax I was charged all the way up at Mt Vernon. This is MUCH closer and cheaper, WIN WIN in my book. If anyone is interested the place its on Westchester ave between Glebe and Castle Hill, right under the Planet Fitness.
He did tell me that he wont be able to refill expired tanks. He made a point of telling me because I told him my last refill was at Mt Vernon and he said he had a problem with a customer who used to refill at Mt Vernon and they didn't mind the expired tank. The customer was furious because it was never an issue in Mt Vernon.
I guess since Mt Vernon is not part of NYC and NYC does have strict rules on everything and anything, then they just don't want to loose their permit or whatever that it is they need to refill co2 tanks.
Hope this helps anyone in the Bronx who needs to refill a Painball tank.