This is my favourite gun I have ever made (out of k'nex). It is a working model of Gears of War's Gnasher Shotgun (my fav video game gun).
This is a 8 shot semi automatic RBG. Different from other RBG's, you must break the lever (bring it forward) to initiate another shot. The gun is capable of taking heavy pressures, so feel free to lay on the elastic power.
I apologize in advance for some of the pics having poor picture quality. Just ask if you need clarification on any of them.
Hope you guys enjoy this as much as I do.
Ps: if you hold the lever forward and then shoot, all the elastics fly off at once.
Step 1: Build the Hand Guard (lower part of the lever)
Build exactly what you see here to construct the hand guard part of the lever (the part you put your hand in. The upper part also acts as a trigger guard.