The spacing of the 2 gears that make up the repeater mechanism at the heart of this gun was adapted from MrRadicalEd's RBG Repeater, because it's so simple and works better than all the more complicated ones I've made or tried.
Picture 1: Complete "Gunzo The Great"
Pictures 2&3: Shows my adaptation of MrRadicalEd's 2 gears. (just a model demonstrating the size and relative positioning of the gears)
Thanks to MASTERMIND for the piece count:
6 white connectors (8-way)
38 yellow connectors (5-way)
6 green connectors (4-way)
20 red connectors (3-way)
4 light gray connectors (2-way)
2 dark gray connectors (1-way)
2 blue tabless (or tan tabbed) clip connectors
97 green rods
34 white rods
9 blue rods
7 blue spacers
Step 1: The Gun Sides
Note, the Red Connector in the middle is missing in a few of the later pictures. That was a mistake. It is always supposed to be there.
Step 2: Trigger And Spinner Wheel
Picture 2: spinner wheel
Step 4: Handle Pieces & odd parts
Pic 2: Make 2 of these. We'll call these "Handle Spacers"
Pic 3: Make 1 of each of these. They are the "Red Handle Base" and the "Yellow Handle Base"
Pic 4: These are called "Through Rods" or Thru-rods. (All Orange connectors are temporary)
Pic 5: These are Side Clips. You'll actually need to take the grey connector off of the white Snowflake connectors, and replace them at the end of step 9.
Step 5: Assembly: Trigger area
Pic 2: Turn it back over
Pic 3: Hold Trigger pieces as shown
Pic 4: Place Trigger on Front Thru-Rod, and a blue spacer on Rear Thru-Rod
Pic 5: Add Spinner Wheel. then another Blue Spacer to rear Thru-Rod
Pic 6: Add Orange connectors to both Thru-Rods. These are just temporary.
Step 6: Assembly: Handle
Pic 2: Add Red Handle Base
Pic 3: Add a handle tip as shown
Pic 4: Add all handle tips
Pic 5: Add handle spacers (gun has been rotated, but not flipped)
Pic 6: Add second handle spacer (the gaps are not necessary)
Step 7: Assembly: Barrel Top
Pic 2: Attach yellow connectors as shown (I used grey ones so you could see the layers better)
Pic 3: Attach 2nd yellow/grey
Pic 4: After attaching 3rd one, you can add the green rods
Pic 5: Repeat steps from Pics 2-4, to create the second internal layer
Step 8: Assembly: Barrel Bottom
Pic 2: Add 1 green rod to the bottom of each of the 6 center yellow/grey connectors)
Pic 3: Attach a yellow connector to the blue rod. See pic note.
Pic 4: Then slide the yellow down to snap into layer 2. Add the green rod.
Pic 5: Make 2 pieces like the one shown here. The other is shown already attached. Do it now.
Pic 6: Repeat steps from Pic 4-5 to finish layer 3
Pic 7: Add final barrel piece, then insert green rod where pointer is pointing
Step 9: Assembly: Finishing up
Pic 2: Add second gun side, sliding over thru-rods, snap into place.
Pic 3: Add blue connector to rear thru-rod. Add orange connector to front thru-rod
Pic 4: Snap in blue rod, with 4 blue spacers
Pic 5: Remove orange connector from front Thru-Rod, replace with white "snowflake" connector. repeat on both sides, making sure they're oriented the same way.
Pic 6: Rotate the snowflake clockwise until the blue rod is in the SouthWest corner, and the other blue rod is straight below the center. It will be tricky to work it past the other blue without disconecting either. Attach green rod and grey connector as shown. Repeat on both sides.
Pic 7: Attach Side Clips as shown, on both sides.
Pic 8: Arrange trigger spacer and rubber band as shown, the spacer will keep the RB from getting chewed up as you fire the gun.
Pic 9: stretch rubber band over tip of gun and seat as shown
Pic 10: Insert white rod through base of trigger.
Pic 11-12: Use a rubber band to secure the white rod in place. Pattern doesn't matter, it just needs enough tension to not slide out.
Step 10: Loading Rubber Bands & Trouble-shooting
Pic 1: clip Rubber band in gun tip. Stretch to the spinner wheel.
Pic 2: Insert the rubber band behind the first white rod that is pointing backward.
Pic 3: NOTE: make sure you get the RB in the V of the connector,
Pic 4: WRONG WAY: If you do it like this, the rubber band may get stuck, and misfire.
Cock the gun by pulling the wheel backward until it clicks once.
Start again at step 1. Always put the RB on the rod in the position shown in Pic 2.
When you go to fire the gun, the first time you pull the trigger, it won't shoot. Rubber bands begin to release on the second pull.
PROBLEMS: If you pull the trigger once, and all rubber bands fly off, you may have put on too many Rubber bands. It all depends on the type of RBs you're using, and the stiffness of your Knex pieces. Try this. Load only 2 RBs. Fire the gun. If the rubber bands shoot individually, as intended, reload the gun with 3 RBs and see if that works. Keep working up until you know the limit of your gun. If the gun still misfires with only 2 Rubber Bands, make sure all the connectors are snapped, especially inside the trigger chamber. If that still doesn't help, try bigger RBs or shorten the barrel of the gun.
Step 11: Variations
Pic 1 - Overview of the Original Build of the Semi-Auto Assembly on the pistol. Here you REALLY see the similarities to Mr Radical Ed's.
Pic 2 - Overhead view of pic 1
Pic 3 - My sniper variant - Shoots 12" bands I got at Staples / Office Depot
Pic 4 - Sniper Semi-Auto Assembly
Pic 5 - Barrel Detail for the Sniper Rifle