The Ultimate Knex (Autoload) Rifle




So this is my favorite design of all my knex rifles and the first one i have posted on this site. This rifle uses a hopper to reload. I usually made my hoppers out of a plastic or cardboard material which worked very well. But oodalumps had a hopper that used all knex pieces so I just borrowed his idea with slight modifications.

Step 1: Construct Firing Pin

1 black/grey rod
2 blue rods

1 red connector
1 grey connector
1 blue and purple joint connector

Step 2: Construct Back Handle

4 green connectors
2 blue and purple joint connectors
3 red connectors
2 orange connectors
12 yellow connectors (as many or few as you want)

4 green rods
5 blue rods
2 red rods
3 white rods

Step 3: Construct Ammo Hopper

12 grey connectors
2 light grey connectors
4 orange connectors
2 white connectors

5 yellow rods

Step 4: Construct Barrel (part 1)

15 peach connectors
1 orange connector
4 yellow connectors

3 red rods

Step 5: Construct Barrel (part 2)

add a grey rod connected to a orange connector to the step 4 barrel

picture shows bottom view

Step 6: Construct Barrel (part 3)

add 11 grey connectors to fill in the gaps in the barrel

Step 7: Construct Trigger

1 orange connector with rubber band slipped through hole
2 grey connectors

1 blue rod

Step 8: Add Trigger to Barrel

connect the blue rod to the orange connector of the barrel. connect it so that the orange connector of the trigger is separated by the orange connector of the barrel by the two grey connectors

Step 9: Construct Front Handle (part 1)

2 white connectors
3 orange connectors

2 yellow rods
2 blue rods

Step 10: Construct Front Handle (part 2)

add two more red rods on either side of the original red rod

Step 11: Construct Connection of Handle to Barrel

two objects:
1 light grey connector
2 yellow connectors

5 green rods
1 grey rod
1 red rod

1 light grey connector
2 red connectors

5 green rods
1 grey rod

Step 12: Connect Step 11 Objects to Barrel

turn barrel upside down and place step 11 objects next to it like the picture.

connect green connectors of the step 11 objects pointing toward barrel to all but one of the barrel's yellow connectors. The green connectors will connect to the diagonal claws of the yellow connectors

Step 13: Connect Handle to Barrel

connect step 10 handle to the barrel. The light grey connectors on the barrel are at the front of the gun. So place the step 10 handle with the white connectors connecting to the green connectors of the barrel. The yellow rods of the handle should be pointed toward the front of the gun.

Step 14: Connect Hopper to Barrel

This step is easy. Simply connect the orange connectors of the hopper to the red rods of the barrel. Put the orange connectors in the gaps of the peach connectors. There should be three peach connectors inbetween the orange connectors of a side and two peach connectors on the outside.

Make sure that the light grey connectors are close to the back orange connectors (not the front orange connectors)

Step 15: Construct Wheel System

This is optional but recommended.

First construct two small objects as the first picture shows.
Each small object has:

2 orange connectors
2 red connectors

2 white rods

Then construct the wheel hold which consists of:

2 red connectors

2 white rods
2 blue rods
1 yellow rod
2 small wheels

Connect the two small objects to the wheel hold as shown in the second picture

Step 16: Connect Wheel Hold to Barrel

The orange connectors of the wheel hold will be connected to the yellow rods of the handle (step 9,10)
Connect them so they are next to the three orange rods on the handle. Then connect the two white rods of the wheel hold to the light grey connectors of the hopper

The second picture (although blurry) shows sentences 1 and 2

Step 17: Connect Back Handle to Barrel

Connect the step 2 back handle to the barrel.

Connect the green connectors of the back handle to the blue connectors of the front handle (step 9,10)

Then connect the top blue and purple joint connector of the back handle to the grey rod coming out of the back of the barrel

Step 18: Connect Rubber Bands

Connect the rubber band of the trigger to the closest blue rod of the front handle (part 9,10). Depending on the strength of the rubber band you might need to wrap it around the blue rod several times so its tight (1st picture)

Then put two rubber bands on firing pin so they are encircling the blue rods (2nd picture)

Then slip firing pin in barrel with grey connector (the hole part of it) of pin sliding in the grey rod shown in step 17. Wrap the rubber bands of pin around the wheels (3rd picture) and then slip on the tip of the two highest red rods of barrel (4th picture)



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    79 Discussions


    8 years ago on Step 18

    awsome gun but i dont like the trigger could be better


    Reply 9 years ago on Introduction

    Ok this comment is a year late but would the chainsaw have to be motorized?
    Pre ferably not because shooting a chainsaw with my motor on it isnt my favorite thing to do.


    Reply 9 years ago on Introduction

    there is an electrical mechanism that ignites the chainsaw motor after it leaves the launcher


    RPC, lol, thad be hard fitting a motor into that chainsaw, so tiny. Im making a rocket propelled knife launcher thingamaboogiglydaboo. Im making knex then a real one


    10 years ago on Introduction

    'But oodalumps had a hopper that used all knex pieces so I just borrowed his idea with slight modifications.'

    I love this phrase, I JUST borrowed this. You know I JUST invaded poland for no apparent reason, I JUST dropped a nuclear bomb on Nagasaki and to finish it off I'm on my way JUST dropping another on Horoshima!

    You would think this comment would have a point, would'nt you? Well your wrong because it does'nt, I'll just carry on talking... ... ... BLAH ... ... ... BYE ... ... ...

    2 replies

    Reply 10 years ago on Introduction

    A hopper is a bucket that holds ammunition which uses gravity to pul the bullet down to where the firing pin will move through... launching the bullet... If you play tennis you'd know that a ball hopper is similar to a hopper on a knex gun...


    10 years ago on Introduction

    is this just a pull-back-the-pin-and-pull-the-trigger gun or is there something I KNOW will make me want to build it? Even if that's all it is, kudos on the design it looks snazzy. lol, snazzy

    1 reply