Requires 24 knex pieces, two small rubber bands, and some tiny rubber bands for ammo (brace bands work).
Step 1: The Grip
Step 2: Barrel and Trigger
Step 3: Loading Mechanism
Step 4: Putting It All Together
You may have trouble with the black rods, so you can remove them then put them onto both segments at once.
CONGRATULATIONS!!! You have finished the building. To load, place one end of the rubber band around the purple piece, and the other around the black rod closest to pointing up. (To add more: push the black rod behind the one with the band loaded on it down towards the grip until you hear the trigger pop, then repeat the first part) Then pull the trigger back until you hear one pop. Release the trigger. If you hear two pops, you jammed it. To unjam, pull any black rod (on the loading mech.) back until the trigger falls back into place.