Knex M4 Carbine (True Trigger)




A working Knex M4. Fires using a new sear system that allows for better firing. NOT A BLOCK TRIGGER, TRUE TRIGGER SYSTEM!!! Fires approximately 50 feet, much more if you add more rubber bands, can handle a lot. Single shot only, but can be adapted into a magazine type gun quite easily. I will follow up with SOPMOD extras if someone else doesn't first. Sorry for the blurry pics, I need a new camera...

(Most counts are an approximate, I just took a quick count)
Green rods: 100
White rods: 75
Blue rods: 21 + 1 bendable
Yellow rods: 4 + 2 bendable
Red rods: 2
Gray rods: 26 + 1 black one (firing pin)
Gray connectors: 70
White connectors: 4
White "Snowflake" connectors: 27
Red connectors: 33
Green connectors: 110
Yellow connectors: 61
Blue "Snowflake" connectors: 10
Purple connectors: 4
Gray gears: 2
Tan clips: 4
Blue clips: 1
Y-shaped things: 8
Hinges: 3
U part of joint: 1

Step 1: Front Handgrip

This is the front handgrip, one distinctive feature of the M4. Assemble in order, follow the directions EXACTLY. READ THE NOTES. THEY WILL HELP YOU FIGURE THIS OUT. Something may seem like it changed, but it is probably the other end. This was an extremely difficult part to photograph, so sorry if it's a little confusing. Last revised 11/29/2008.

Picture 1: Expand this out until it is 12 long on each level, 24 long total
Picture 4: The rods don't actually fully snap into a place, however, they are wedged in there as show. Therefore, they will make a soft click if they're in place, and will slide smoothly back and forth.
Picture 5 & 8: These pictures are at opposite ends of the barrel. The orange pieces are snapped on the same way at both ends here
Picture 11: This is just a ramrod, do not add this if you plan on using a magazine system with this gun because it effectively plugs the barrel
Picture 14: The gray connectors between the white snowflake and orange connector can be cut; you can cut the tops off of them, because this is where the magwell will eventually go.
Pictures 15 &16: This is just a suggested barrel design, i was almost out of pieces so whatever i had i used for it, feel free to make a better barrel.

Pictures 4, 5, 9, 10, 11, 12, and 13 are the FIRING END of the gun
Pictures 6 - 8 are the BODY END of the gun.

Step 2: Upper Reciever

The upper reciever portion of the M4. The light blue rod on the back IS one of the bendable blue rods which are very rare; I only have 4 of them from one set. You can make it a straight magazine like the Vietnam era guns, and that would probably be the best way to make a working magazine.

Step 3: Carrying Handle

The distinctive carrying handle for the M4.
PLEASE READ: In the middle, it should not be a white snowflake, it should be a yellow "half snowflake." This allows you to look down the valley of surrounding snowflakes to actually use the sights

Step 4: Lower Reciever

The lower receiver portion of the M4. Contains the true trigger portion, and the sear catch. I took pictures from only one side, but it is exactly the same on the other side.
Picture 2: When referring to the triple greens snapped onto the yellow rod, after a few shots, the top part of the middle one will snap off. It's nothing to be concerned about, just realize that it will happen.

Step 5: Firing Pin and Charging Handle

Firing pin and charging handle.

NOTE: PLEASE READ:!!!!The firing pin only has ONE blue connector, NOT two as it shows in the pictures. I took the pictures then realized that it was wrong when I was putting it together.

You should duct tape the part of the firing pin where it goes hinge half-tan connector-blue connector, I didn't to show what it looked like and because I'm out of duct tape. Also, it wouldn't hurt to have all black rods here (they're stronger) because of the stress that gets put on this portion of the gun.

Step 6: Stock

I only took one picture of the stock. all across the top, it should be solid, "5-across," so the charging handle slides on it smoothly.

Step 7: Assembly

Assembly for the entire thing. Note the placement of the multiple rubberbands.



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    299 Discussions

    The concept of a sears is different than that of the typical 'block trigger', because it catches the ram instead of blocking it from the front. Believe me, if you had been around in 2008 on this site you would refer only to KillerK style triggers as 'block' triggers and nothing else, because so many were posted that, though others technically block, anything else was considered far too advanced to be lumped with block triggers. It's a trigger type, not an overall classification.

    There are specific names given to specific things sometimes. "Block trigger" is the name we have given to a connector(usually orange) that is centered onto the side of the main barrel and acts as a gate that lifts in an arced path to move out of the rams path. Best example- KillerK's original pistol. That is what we call a "block trigger". This is not a "block trigger", this is a "sears catch", which snags the rear and of the ram and holds onto it. You can look at everything and find similarities but it is the differences that define.

    You are also missing my point.
    Every kind of trigger either catches or stops something. The trigger mechanism BLOCKS a piece from moving and hitting the bullet/firing rubber bands.
    When you pull the trigger, it releases the firing mechansim and fires the ammunition that the gun uses.

    Oh my goodness child, I'm not an imbecile. I understand this full well, but that does not change the fact that different trigger types have different names. "Block trigger" is a name.

    Yes, they are, but that does not mean that it is a "Block trigger". I'm repeating what I'm saying over and over and you're just throwing the same thing at me without grasping my point. It is a trigger that blocks, but it is not a bloody "block trigger". This uses a Sears, which, although blocks, is a very different system. I really can't keep saying this lol.


    Reply 10 years ago on Introduction

    I knew you would say that. And I also know the next thing you will say. XP


    Reply 7 years ago on Introduction

    Time is not my master! (trying to imitate my sense of humor at 17, I'm finding it difficult, so maybe it is)


    8 years ago on Introduction

    Sorry, not to disappoint everyone, but I built put on the maximum number of bands that the firing pin can hold and the gun only got to 25 feet. If you want to prove me wrong go ahead and post a video. Sheesh, I hate it when people lie about range just to get views.....