The A1.2 Mini Lego Assault Crossbow




This is the second modification of the A1, and probably the most significant one. This new crossbow can be disassembled into 5 pieces, and then reassembled into the crossbow in under 30 seconds (my record is 27 seconds anyway). It also features a new type of trigger: a modified gear trigger, which instead of having the interlocking gears inside the gun, the interlocking gears are to the side of the crossbow (this saves on space). The length of the crossbow has also been slightly shortened, and a new sight added. The gun fires a 2x4 (F) brick (F means with a flat piece on top). It has a range of 35+ feet (depending on rbs) and it is very powerful and accurate.

Improvements over A1.1:

-Can be disassembled into 5 pieces, then field assembled in under 30 seconds
-A new, reliable gear trigger
-Slightly shorter in length.
-Better sight

My Website:

Step 1: Bottom Connector Piece

This is a very simple piece which is used to connect the bottom pieces of the crossbow when you assemble it.

Step 2: The Rubber Band Holder/Forward Piece

Fairly easy to make.

Step 3: Body/Runway Piece

Also very easy to make.

Step 4: Handle Piece

Short, easy step

Step 5: Mechanism/Back Piece Part 1

This step might take a long time, but it is still easy. The step is so large I had to split it into 2 parts.

Step 6: Mechanism/ Back Piece Part 2

The other half of the back piece.

Step 7: Assembly + RBs + Ammo

The ammo is a 2x4 brick with flat pieces on top. The rbs you will need are 2 regular sized rbs (which are usually pink coloured, but in this case white coloured)used for firing, and 2 smaller and thicker rbs used for the trigger counterweight. The gun can be assembled and disassembled easily, and with practice it can be assembled (with rbs and ammo on it and ready to fire) in under 30 seconds.



    • Trash to Treasure

      Trash to Treasure
    • Tape Contest

      Tape Contest
    • Arduino Contest 2019

      Arduino Contest 2019

    12 Discussions


    7 years ago on Introduction

    Just pointing this out but... None of these are really crossbows. =\. The definition of a crossbow is: A weapon consisting of a bow fixed crosswise on a wooden stock, with grooves on the stock to direct the projectile. These look like crossbows, but you don't really have a bow on there. Bow - a weapon for shooting arrows, composed of a curved piece of resilient wood with a taut cord to propel the arrow. So my point is... These are crossbow shaped slingshots. Not crossbows. Just sayin'. 

    1 reply

    7 years ago on Step 7

    where are the wheel things that you put the rbs on


    8 years ago on Step 3

    I can't find the two 2x1 in picture 4 with two holes in each one. Is there possible to use ones with one hole by any means?

    1 reply
    Doctor Freeman

    9 years ago on Step 7

    y do you need the counter weight rubber bands because on ure site u said u wouldnt need them tobe stronger?


    9 years ago on Step 7

    better then my old semi but simpler that is awsom!!!!!!!! :D


    9 years ago on Introduction

     Do you think you could make a semi-auto pistol that shoots rbs? not bricks? cuz my parents think its a little dangerous. And i was just about make the C3.3...