Please make sure you read all the notes carefully. The last 3 pictures are the same rubber band.
Step 7: How to load and fire
Pull the ram rod back, load the magazine (Normal version holds 3 bullets). Aim and shoot, pull the trigger back and push the red rod up (picture 2). The 'shell' will fall out. Push up the rod fast, otherwise two bullets will fall out (Becouse of the magazine pusher).