Been messing around taking apart nerf guns see how they work also took apart a couple knockoffs. Challenged myself to come up with my own design and this is the result after messing around on and off for about a year I finally printed a version that works this is the 4th generation.
Coming soon 3D Printed Nerf Double Barrel Shotty...
I left the gun mostly blank except for shameless promotion but I would really like to see everyone go at it and remix remake retweak to your hearts desire right now it shoots about twenty feet all nerf guns have to shoot 75 feet so help me remix this thing and get 75 feet. Also trick it out!!!!
Okay so you will have to scale these models by x1.15 ... this will basically allow the dart to slide into the nozzle. I printed out a bunch of different sizes and this seemed to work the best,,, I would also try x1.16 it may be too loose or just right... depends on your printer...You will need 4 different springs for this gun and 3 o-rings you can find the springs at a hardware store they do not sell the right ones at blowes or homecheapo .... You will need to use ABS to Abs glue.. not transition glue but straight up ABS glue, also grab some plumbers grease or heat grease.. you will need to coat the o-rings so they glide in the pipe.. https://www.youtube.com/watch?v=tPKA3qQfgOA&feature=youtu.be