Make theese, if for some reason you can't tell there are eight of theese.
Step 2: Step2: yet again, very simple
Step 3: Step3
Sorry for bad pic but, I think you can figure it out.
Step 4: Step4
Place ruberband around one of the pullies, as this will be diffucult but possible later on.
Step 5: Step5: almost done
Put theese together so you get this,(see below)
Step 6: Step6: the final touches
Make this. (3 blue spacers = 1 grey) also the green rods are the same as red rods.
Step 7: Step7:done
Attach what you made in step 6.
Step 8: Step8: loading and firing!!!!!!!
When you load push the grey rod inbetween the orange and brown connectors in the middle. I would suggest cutting a slit in the end of the grey rod (ammo) but, be careful as shown in pic2,ouch that hurt my finger. When your done it should look like pic3 when loaded.