AP2 Slide Pistol Upgrade From "simple K'nex Pistols"

About: I like to think of myself as someone who only satisfied with high quality projects, and "whats's it matter to ya, when you got a job to do, you got to do it well, you got to give the other fella hell!" - Gun...

This istructable is to show how to upgrade the previously posted "simple k'nex pistol" to an AP2 slide-locked pistol. (still single shot).

Differences: obviously, instead of pulling back the firing pin, when you slide back the pistol slide, it slides back the firing pin, then locks it it with the new lighter trigger design. Also, the grip has been strengthened dramatically, and improved sights have been added. This version can also support heavier elastics for an exponentially stronger shot and hyper-accurate range with small-medium projectiles (green, white and blue rods-best with white)

Again, the tension on the connector on the firing pin is too much, so superglue or tape the crap outta it so itll stay on.

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Step 1: Base Deconstruction: Deconstruction of the Pistol and Frame

This one's easy. first, remove all the elastics, then the trigger. You will later alter this and the slot in which the connector blocks the barrel for a smoother, more hair-pin style trigger.

Step 2: Remove Grip and Frame From Upper Barrel Components

Easily detach the upper reciever (barrel assembley) from the frame.

Step 3: Remove the Grip From the Frame

Detatch the grip from the frame, it will later be reinforced.

Step 4: Deconstruct the Top Part of the Reciever

Detatch the upper part of the reciever/barrel assembley, so it looks like the pic below. discard the parts you removed.

Step 5: Begin Alterations: the Trigger

Simply modify the trigger so the white rod that supports the orange connector to the second postition (45 degrees) on the red connectors.

Step 6: Modify the Frame

This one is simple. just flip the tan connectors on the white rods the other way around, then add the three yellow rods to the upper frame.

Step 7: Modify the Grip

Move the small black connectors with the ball on top to the two yellow rods directly behind where they used to be. Then remove two of the five existing red connectors, and make the rod, spacer, and hinged connector component. it will come into play later.

Step 8: Modify the Lower Reciever/barrel Component

This is slightly more complex. detach the long gray rods at the front of the barrel. remove all three of the white connectors, and add in three yellow connectors in their place. Where the single gray spacer was, add in another single blue spacer. This will allow more room for the improved trigger to funtion, making it a smoother and lighter pull.

Also, it is critical that you add the green rods exactly where they are shown, as to not impare the structural strength of the gun.

Step 9: Build the Slide

Now, just build exactly what you see in the bottom pic. If you want, to improve the sights, replace the back gray connector to a black connector that is used to hold the elastics onto the firing pin. It allows for a ball-and-cup type sight for easier target aquisition.

Step 10: Modify the Firing Pin

Below is a side by side comparison of the old and new firing pins. the new one has the two gray rods to slide into both the bottom of the slide, and the barrel.

Step 11: Begin Assembley: Frame and Trigger

Snap in the yellow rod for the trigger to the 90 degree slot on the yellow connectors.

Step 12: Attach the Frame and Grip Together, Then to the Barrel

Sorry I didnt take a more detailed pic, but attach the grip first so the 45 degree rod on the yellow connector with 2 gray connectors, then again, to the bottom of the frame as you did with the last pistol.

Attach the frame to the pistol also like you did the last one, making sure to attach both of the hinged connectors to the corresponding green rods protruding from the bottom of the barrel/reciever.

Step 13: Attach the Slide

Using the two long gray rods that were slid through the gray connectors at the bottom of the barrel, attach them to the top of the barrel/reciever. Attach them to the corresponding snap locations on the three yellow connectors.

By the way, the two small black connectors on the back of the sliding rods are to guide the firing pin elastics to keep them from pulling down on the firing pin when loading.

Step 14: Slide in the New Firing Pin

slide in the new firing pin, black connector down into the top and bottom chambers of the back of the pistol. You have to have the trigger in the depressed position to slide it all the way through if you have assembled everything perfectly.

Step 15: Attach the Elastics

Attach all three elastics for: the trigger, the slide, and the firing pin. Anchor them all to the locations specified in the bottom pics.

Step 16: You're Done!

for now, this is the most up-to-date version of the knex pistol. If you have finished it correctly, you have successfuly upgraded your simple knex pistol to the AP2.

Now, go and shoot stuff.

Step 17: Loading

If you cant figure it out, let me help you. Slide back the slide ALL THE WAY until the back two gray connectors of the slide hit the small black connectors on the slide rods that redirect the firing pin elastics. To make it easier, hold down the trigger so the pin can move all the way back without making it more difficult.

then, load a white rod into the muzzle, aim with the sights, and witnes the very surprising accuracy that comes with your upgrade to an AP2 pistol.

Step 18: Custom Upgrades: AP2 Mk.2

Here, I just modified the rear sights, shortened the thumb guard (back) and the rear of the slide.

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    118 Discussions


    if you guys like rbg's, go to my forum topic: "high quality rbg's"- you might find something to your liking there.


    i mean im just 13 and my parents wont let me buy any weapons like arisoft guns OR replicas/RBG's like you make... what are the RBGs made of?


    Oh, sorry. Hell no, it won't break from 2 meters. It's strong if it's one solid peice especially, but why would you drop it from two meters anyhow?

    hey mmzdaniel just build knex guns without your parents knowing. i keep mine in a safe compartment near my desk in a secret drawer. and since its the summer, my parents are usually busy working or somewhere else, allowing me to play with them with no fear!!!

    i am allowed to have knex guns but not airsofts or replicas of guns.... and the problem is, my mom wants everything in my room clean and organized, so she cleans it her self. i cant hide stuff like that!

    why dont you get an airsoft or bb gun and build a knex frame so it looks like a knex gun? that way you could fool your mom and your friends (they'll think you'll shoot a harmless knex piece at them then BANG!!! you shoot them at close range and then they go WTF???) also, do you have a cupboard or drawer NOT in your room that is yours? you could hide it there. or wrapped in clothes.

    thats a great idea! and yes i know where to hide, i got a good place. the only prob is, they dont sell airsofts near my neighborhood, and i need to get a car. (and license) lol... so i cant do that. but my grandfather might give me an airsoft....

    buy it online or get one of your older friends to get it for you. or just smuggle it. you could also buy it on ebay, and since its the summer, you would could check the mail every morning so your parents dont see it.

    i dont have my own credit card, and my friends buy their airsofts in places that are to far to go on foot.... or bike.... and how do you think i could smuggle them lol?

    you could try googling a random credit card number, but you might be arrested. howabout when you go on a trip or something, you could try sneaking in a purchase without your parents knowing. by the way, how old are you? like seriously, so i know your physical capability of sneaking in things or what not.