One final adjustment to the design that I made was to remove the prongs on the slider that held the elastic band. I removed these and added a cut-out in the middle layer of the slider so that the band could hook around the screw. This meant there was no chance that the bands could come off when firing.
Once I'd tweaked the bits I wanted to, the final design was laser cut from 5mm acrylic.
The files in this step are provided for personal use on the condition that they or parts cut with them aren't sold.
The pistol's bolted together with M3 machine screws and nuts. The end plates and slider are spaced with washers so that the plunger doesn't get caught on the end plates, since it's the same width as them.