The D3.1 Lego Semi-Automatic Handgun Mod

This is the first mod of the my previous D3 semi-auto handgun. There are a few improvements I have made in this mod, such as:

-It now has a 7 round capacity (there was a 6 round capacity in the D3)
-Improved magazine design (sturdier)
-Magazine can now be used as a suitable handle
-Magazine will not accidently slip out now (area around the mag has been built up slightly to atop this)
-More counterweight rubberbands can now be added without breaking the gun (to prevent accidental fire, and double-fire)
-Improved forward sight (this sight will be pointing perfectly straight, it won't be crooked, or won't fold down)

**NOTE: TO DO THIS INSTRUCTABLE, YOU MUST FIRST BUILD THE D3 Semi-Automatic Handgun from it's instructable: D3 INSTRUCTABLE**

The video is from the D3 Semi-Automatic Handgun, but even though this is the instructable for the D3.1, they fire exactly the same.


Step 1: Area Around Magazine Improvements

With this step done, you can now add more counterweight rubberbands onto the trigger (I added 1 more and that was fine for me).

Step 2: Magazine Improvements

Basically, you need to change the very top piece of the magazine, the part which holds the rubberbands (change from the 1x4 piece with 3 holes, to a 1x2 piece with 2 holes, on both sides), and extend the length of the magazine, as well as adding a new piece design to the bottom.

Step 3: Top Sight Improvements

This sight is just more practical to use.



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    9 Discussions


    9 years ago on Step 1

    ive added another rubber band to the trigger but it still fires all of them at a time?

    1 reply

    Reply 9 years ago on Step 1

    Heres a bunch of things it could be: 1)Use less thick firing rubberbands (I used #64s) 2)Check to make sure its made properly 3)Add on another counterweight rubberband if its not that (the counterweight rbs should be fairly small, not easily stretched, meaning it will be a much stronger counterweight rubberbands) 4)Also, check to make sure that the gears on the side of the gun are all aligned. If there not, then theres nothing to stop the firing gear from spinning freely.