-Semi-auto (you choose you ROF)
-Reliable trigger mechanism
-Uses a lot of pieces
-Takes a long time to load if you don't have experience (loading gets faster with practice)
More Instructables by me.
Images 1-2: Loaded with additions.
Image 3: Loaded without additions.
Step 1: Barrel: Step 1
Images 4-7: Place the parts on gray rods as shown until you get image 8.