K'nex 'semi Pump Action' Gun

About: Hey there. I won't add too much info here, as it'll show up as one big paragraph. I'm not super active anymore, on here.
Hi there. I made this gun today, and wanted to show it. It is a repeater (it shoots), and reloads the bullets from a tubular magazine underneath the barrel. With semi pump action, I mean that you  have to cock the pin manually, but you chamber the bullets via a pump. I had this idea a long time ago (a very bad prototype is on Mahmel's orange board), and decided to do it again.
I hope you like it, and please comment. Help is also appreciated, as it isn't near perfect yet.
It holds 3 bullets (in the video that's coming up soon, I only used 1, as I didn't cut the needed y-connector correctly
Update 1: 
- Cut a y connector in a special way, makes the feeding much smoother (this one was also needed on Bakenbitz's original mech)
- Made the barrel 1 connector longer, and added some sort of hop-up
- Different stock
- Different barrel internals. Bullets don't become stock anymore

- Bakenbitz for his lever action gun. I used the bullet ramp in a modified way, to incorporate the pump.
- Killerk, for the idea of the hop-up (inspired by this add-on on his Z35)

Video of the new update:



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    38 Discussions

    Thanks. I can try the PDW-57, but after I posted instructions for this. I hope to have these finished on Thursday (my shortest schoolday), but I have exams from Friday 'til next week Friday, so I don't know when the PDW'll be finished

    Yeah. I posted the instructions for this one yesterday. Maybe I find some time tomorrow, or already later today, to start the PDW


    6 years ago on Introduction

    Cool, but whats the point of pulling the pin back then pumping it when you could just pull the pin back on a regular gun?

    1 reply

    I am designing something a little similar to this. Except it as a vertical (as in up and down) removable mag, and I'm trying to allow the pump on my gun push the bullet from the mag into a separate chamber as well as pushing the firing rod all at the same time. It's going to be an innovative kind of gun.

    5 replies

    Sounds cool! I had that sorta idea in my head for a tubular mag, but then I realized that with tube mags, the pin pull would be very short. So I made this. Looking forward to see what you come up with


    I'll maybe post them today. I've fixed the barrel and feeding problem, and made a (in my opinion) better stock for it.