Nerf MicroShots Zombie Strike Hammershot, Ages 8 and Up - Walmart.com
AKBM 7 Darts Brass Tube Cylinder for Nerf HammerShot | AK Blaster MOD
7 Round Cylinder Barrel Mod - For Nerf Zombie Strike Hammershot Blaster Revolver | eBay
Rival Hammershotty - a 15round Hammershot Mod. If there is enough interest, I may put this mod kit up on Etsy. Let me know if you would pay $20 or so for