I apologize for the long wait, but my schedule has been busy. This is the second version of my arm-mounted rubberband gun, it can hold around 64 rubberbands (depending on the type you use)
I will try to post my reinforcement mod soon that lets it hold many more rubberbands (80-96) right now i do have this easy reload mod

pros
1. super cool
2. holds a lot of ammo
3. can be easily modded for ones personal preferences

cons
1. takes a LONG time to reload
2. not the easiest to load
2. kind of heavy
3. hard to run fast with

I would like to thank MrRadicalEd for his repeater mechanism

here's the vid, sry about my bad shooting method

Step 1: Build the Barrel Segments

the hardest thing to build is the barrel.

part 1
1. what you will be building (you will need eight of these)
2. finished part 1
3. build this stuff
4. everything together except the top layer
5. the top layer on, add the rubber band
6. close up of how the rubber band goes

part 2
7. build two of each
8. add blue rods to one
9. put them together, get blue rods ready
10. put the rods in.
11. the two parts, make sure to flip part 2 over like in the picture
12. close up
13. parts together

Step 2: Put Them Together

1. add green connectors
2. a rear view
3. stop when you get a half circle
4. notice the blue rods on the green connectors
5. here too, on the other side

Step 3: Make the Handle

1. the finished product
2. build these
3. put it together like this
4. get these
5. put them together, it may be a little tricky once you get near the end.
6. it put together
7. the three parts
8. put the three parts together
9. where it goes on the gun

Step 4: Finishing Up

Put the rest of the guns on and it should look like this. to shoot: put you hand in it and use the other hand to move the triggers back and forth, when one barrel runs out, turn it and start shooting the next barrel. thanks for looking and I hope you can build this (I don't make the best instructions, sry) comments and suggestions are welcomed.