Lego A2 Powerful Mini Crossbow

This is the sequel to my smaller A1 crossbow. This crossbow is ALOT more powerful, because it can shoot 30+ feet (depending on rbs), can dent cardboard (keep in mind, this is lego, not sharpened knex), and is very accurate. The only downside is that this crossbow is larger than the A1, but it is still fairly small. It also has a new type of sight on it, which is kind of like the Ak47 type of sight. It makes it alot more accurate. The crossbow also has a new type of trigger, a system which uses 2 gears to fire. The crossbow fires 2x2 bricks, with a flat piece on top.

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Step 1: Bottom Add-Ons

In this step, the handle and the trigger holder is made.

Step 2: Trigger

The trigger and the pivot pieces for the trigger.

Step 3: Base + Attaching Add Ons to Base

Here we make the base of the gun, and we attach the trigger and the holder thing to the bottom of that.

Step 4: The Ends of Crossbow (RB Holders)

The 2 sections of the end of the crossbow.

Step 5: Another Thin Layer on Top, and the Back Part

Read the title

Step 6: Firing Gear and Completion of Runway

The gear that holds and fires the rubberbands is made, and the runway is completed.

Step 7: Sight (Optional)

This is how to build the sight

Step 8: Ammo and Rubberbands

Shows the type of ammo, the rubber bands used.

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    36 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'. 

    3 replies

    When you install the gears you are pushing one gear into another forward causing the top gear to go back. What did I do wrong


    7 years ago on Step 8

    thanks i made it and god its powerful! ive made some changes though. ive got a longer trigger and made different iron sights. again, thanks.

    why not adapt this to shoot pencils instead of lego blocks?
    Just a little carving with the pencil eraser and you got an arrow.

    Doctor Freeman

    9 years ago on Step 2

    on the step with the gears the small one doesent move is it intendended or not


    10 years ago on Introduction

    I made this one like, 5 months ago now.
    It's awesome! Works really good.


    10 years ago on Introduction

    this gun is awesome but the gear where you put the rubberband is to small so i modified it by adding a bigger gear and moving stuff because i use 4 rubber bands and it goes like 5 feet!

    2 replies

    Reply 10 years ago on Introduction

    i used that gear because it is the largest I have, maybe use thicker rubber bands, cause it went like 30 feet with mine.