Masterdude Crank-Opperated, Double-Barrel Gun (MCODBG)

About: I make K'nex guns, specializing in semi-automatic, RBG-Slingshot hybrid systems which i use in most of my guns. Note: I am not responsible in any way for any damage, injury, or death caused by my Instructab...
This is a project I've been working over the last couple months (well, couple weeks followed by months of minor changes and procrastination). When the handle of the crank is cranked, the ram rods are pulled back, and then rapidly released pushing the ammo out of the gun. Honestly, I doubt I'll post this as an I'ble since it shoot rather weakly, but I posted this more to place some ideas which I've used here which some may find useful in their own projects.

Some comments:
  • Cranking it shoots it
  • It shoot two shots at a time
  • The gears make it easier to crank and allows more power, but slows the ROF

Image 1: The gun
Images 2-3: The ram rod, first pulled back, then released
Images 4-8: Converting the rotation of the cranking mech to pulling back and releasing the ram rod
Image 9: The crank mech
Image 10: The gears
Image 11: This allows a more sudden release of the ram rod. It allows the rod to jump forward once the ram rod is pulled back as far as it goes
Images 12-13: When pushed in the pin stops the ram rods from advancing making loading the mags a bit easier. Could also function as a safety



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    11 Discussions


    7 years ago on Introduction

    Maybe if you change the blue gear into a red one and the red one into a blue one, you'll have a higher ROF for the same amount of cranks.

    8 replies

    Reply 7 years ago on Introduction

    But then it would take more force to turn the crank, which may increase break-downs and to make it crankable the amount of rubberbands, and therefore power, would have to be decreased.


    Reply 7 years ago on Introduction

    I tried it but I wasn't able to make one full crank before some connectors started shooting off of the axle.