Introduction: Knex Pistol - Crossbow Style

Picture of Knex Pistol - Crossbow Style

This is technically a crossbow, but it's used as a pistol. It's a crossbow because there is no ram, but there is a trigger. It is powerful with just one rubber band - 15 to 20 ft max range, 10 ft effective range. By effective range I mean the max distance where the round is still moving on a straight path without an arc. This the first gun that I can take full credit for.

Step 1: Gather Parts

the parts you will need are

2 red
3 yellow (required but they will be the ammo)
1 blue
2 white
3 green

12 yellow
1 orange
3 grey angles

5 black clips
6 blue spacers

Step 2: Build Trigger

Picture of Build Trigger

This is a simple step. The picture should explain fully.

Step 3: Build Barrel

Picture of Build Barrel

This is the longest step. The main body of the gun is also the barrel. The series of pictures should explain fully again.

Step 4: Add Rubber Band Handles

Picture of Add Rubber Band Handles

Add pegs for the rubber band and attach the rubber band

Step 5: Add Front Handle

Picture of Add Front Handle

The handle is made of three yellow rods.

Step 6: Loading and Firing

Picture of Loading and Firing

This is a bit complicated and may seem very much like an 1800s style gun, but you'll get the hang of it. First you push a yellow rod into the barrel. The you use the blue rod on the trigger to push it out of the back of the gun. Grab the yellow rod and reattach the blue rod to the trigger. Pull the yellow rod back and make sure the trigger locks. Pull the blue rod on the trigger to fire. The pictures may give more detail.

Step 7: Finished!

Picture of Finished!

I hope you have some fun with this. I haven't yet tried a sharpened point on the ammo. I think it may be more liable to misfire. Leave a comment if you try; I'd love to see how it turns out. Also, try to see how powerful this thing can get. I just got some new rubber bands today, so I'll be trying too.


stact13 (author)2010-03-18

PLEASE! If you happen to find that a few K'nex pieces and rubber bands can be used to fire a small projectile a few feet, DONT post it! Make a real, ORIGINAL gun, and use more pieces than can fit in my hand when disassembled. AT LEAST use a real trigger (block triggers are absolutely useless and just clog the site).

Sorry for this short rant, I get pissed off when people do this, even for their first try. As a rule of thumb, try keeping all 'simple' guns at least as complex as... lets say... these:

TorBomb (author)2008-10-30

once again awsome! i also added a mod. u know that little black piece sticking out the side. well i put a tree point conecter there with a white rod attached. then i put a two point angled conecter on the trigger and tied an elastic to both of them. now it locks the rod in automaticly:)

J-Unit (author)TorBomb2008-10-31

That is really smart. I will definitely try that out.

mettaurlover (author)2008-08-22

sharpened rods make no difference; in fact, they go a little bit farther and a lot faster. and they are slightly less accurate, except at point blank range, where you should NOT fire at anything that lives.

J-Unit (author)mettaurlover2008-08-26

You said the sharpened rods make no difference, and in the same sentence you said they go farther and fly a lot faster. That doesn't make any sense.

Gh{O}sT (author)2008-08-03

I really like this gun.

MI6 (author)2008-06-22

ATTENTION ALL K'NEX GUN-MAKERS or better still ESPECIALLY ww2 gun enthusiasts

Please visit:

knexster (author)2007-07-03

Looks OK but,dude, look around the site before posting
Okay look at this and think if your next gun is worth posting

J-Unit (author)knexster2007-09-08

you don't have to brag about your huge sniper

knexster (author)J-Unit2008-02-24

excuse me, my sniper? thats not my sniper

J-Unit (author)knexster2008-02-26

I'm sincerely sorry for that. It was a stupid comment... ...but I definitely don't think you should be using things you didn't make as backup for an insult. You'll never know until you ask, maybe ipod killer doesn't really care. Also, do you think I really care? Bigger isn't always better you know.

knexster (author)J-Unit2008-02-27

Thats not the point i was trying to make. Look at this crossbow then look at ipod killers sniper ( which is awesome by the way) his gun must have taken at least 6 hours of designing, tinkering, and creating to make it while this crossbow must have only took what, 5 minutes to think up and create? Also, your right bigger isnt always right but complex (with most people) beats simple 9 times lout of 10

J-Unit (author)knexster2008-03-01

Once again, I think not. Complex isn't always better. Some people have more simplistic and minimalistic views of things. It's not fair for you to say most people like complex thing when it may not be true. Have you asked everyone in the world their opinion on the matter? Also, my gun may have taken less time to design because it was simpler than ipod killer's sniper rifle.

knexster (author)J-Unit2008-03-03

I never said complex is better, in fact i like easier versions of guns as long as the idea is complex. Your right i have not asked every single person in the world, but i dont need to. Like i said about 9 out of every 10 people would rather have a fresh, brand new idea then something that a monkey can do with the right training. In the future i hope you look around the site for ideas and designs and dont post a trigger that just flips to the side when pushed down.

ROBOT CHICKEN (author)2007-09-07

(sarcastic) woaaaaaaaaaaaaaaw......woow....cooool (sarcastic applause)

wussap (author)2007-07-13

a crossbow style gun like this? i believe this may be worse than the hundreds of block triggers

goynmilk1000 (author)2007-06-23

Nice it really worked well for me =D

J-Unit (author)2007-06-09

Thanks for your support guys

altaria1993 (author)2007-06-08

no crossbow, neither a gun, just a "device that makes things fly in a somewhat-controlled way" and btw, a crossbow uses a trigger too, i have a toy crossbow (wich i can make about 10 times as strong an a minute) that just works exactly the same as a crossbow, exept it uses a huge streching band except for a actual bowstring, but hey, nice try, but please try making innovative guns too!

knexboi (author)2007-06-05

i like this "gun" but when i add more rubberbands the white(silver) rods just fly off in my direction lol.other than that its pretty awesome

Easy Button (author)2007-06-01

no offense but this is kinda bad

It's a good try! Stop making it sound bad! -J

Darth Trainman (author)2007-06-01

This be no crossbow! Eh?

sammyb (author)2007-06-01

i think it is really good, a new approach to guns, if all guns were the same then the site would be boring well done j unit

Alingarhs (author)2007-06-01

Could we PLEASE stop with these?

Flie-Ing GOOse (author)2007-06-01


Pat Sowers (author)2007-06-01


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