Introduction: Mechanical Pencil Gun

Picture of Mechanical Pencil Gun

An easy to make office weapon capable of firing anything that will fit in the barrel.

Step 1: Gather Materials

Picture of Gather Materials

All you need is a BIC mechanical pencil and two rubber bands. Pencils by BIC are perfectly suited to this (I haven't tried any other models yet). You also need a knife/razor to make an incision later.

Step 2: The Barrel

Picture of The Barrel

To make the barrel, you first need to get rid of the writing cone. The writing cone is the gray cone attached to the clear cylinder in the picture in step one. I find that the easiest way to do this is to let the cone hang off the edge of a desk, and break it off with your palm. Once the cone is off, you should be able to pull the eraser shaft out.

Step 3: Rubber Bands

Picture of Rubber Bands

To attach the rubber band, first put one end around the pocket clip on the barrel. Then, stretch the other end out to the opposite end of the barrel. Once you do that, you can use the second rubber band to tie it to the barrel.

Step 4: Firing Mechanism

Picture of Firing Mechanism

Get the eraser shaft, and make an incision with your blade through the center of the eraser, coming from the top. You want to split it, not cut it off. Then, take the rubber band end off of the clip, and slide it into the notch you've made in the eraser.

Step 5: Completion

Picture of Completion

With the rubber band attached to the eraser shaft, slide it back into the barrel. The gun is now complete. To fire, pull back the eraser shaft, load ammunition into the muzzle, and release.

Step 6: Final Notes and Modification Suggestions

The gun is pretty powerful (but it's potential is defined by the type of bands you use. High-tension bands make the gun much more powerful.), but it does have it's shortcomings. Multiple impacts from the eraser shaft to the barrel chip away at the barrel, eventually making it useless. It's also got a lot of kick, it's pretty uncomfortable to fire if you're using really strong bands (even though some of the bands I used could put a BB through a soda can).

The way I described is the bare-bones assembly. There are many modifications that could increase the longevity of the gun and make it more powerful. On my gun, I took the clip off of the barrel, wrapped the entire barrel in electrician's tape, and proceeded from there. That reduces chipping from the firing mechanism. I also wrapped the eraser notch assembly with tape (just in case, and it makes the gun look more uniform). There is also a part of the eraser shaft that is not as wide as the rest, I cut it off and filed it down, so that the hammer takes up the whole width of the barrel, and leaves some space in the muzzle for ammunition even when the hammer isn't pulled back. Finally, at the firing end in the clear shaft, the opening isn't as wide. You can shave the excess plastic off to make for a uniform barrel width.


em20909 (author)2017-11-13

I'm having a little bit of trouble getting the cone off!!!

supermatthewisbeast (author)2016-01-21

I MADE IT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

me too

swablo (author)2015-08-26

it's awesome thx

follow me peeps so we can make a group and be beast

im with you bro

Hellothere12345 (author)2016-03-10

This will be a good help for a kid Will Salzmann

NolanP2 (author)2016-03-09

What should i shoot

supermatthewisbeast (author)2016-01-21


Spycat2468 (author)2014-01-28

there's an easier way u dont need all that stuff

Herobrian53 (author)Spycat2468 2014-11-17


follow me

Herobrian53 (author)Spycat2468 2014-11-17


listentome (author)Spycat2468 2014-02-26

ever thought of using something those huge rubber bands that are on lawnmowers when yo buy them and a dowel rod thats whittaled down and a pvc pipe with a connector that makes it slighty smaller

Spycat2468 (author)listentome2014-02-26

No i haven't, but i think that would be awesome.

supermatthewisbeast (author)2016-01-21

I made it but i was writing with it and it exploded in my hands causing me to shoot a rubberband at my teacher and me getting a 5 day ISS for Voilence!!!

amirmango (author)2014-11-28

it was awesome tnx

101sugarplum101 (author)2013-06-08

awesome.I made like ten! the kind of amount I used was a part of a paper chip with a rubber band ball on the end. works great:) ( you could also use half a tooth pick;)

101sugarplum101 (author)2013-06-08

awesome.I made like ten! the kind of amount I used was a part of a paper chip with a rubber band ball on the end. works great:) ( you could also use half a tooth pick;)

championx5 (author)2012-09-25

Also, you could take a pen spring and put it on the end of the hammer, then just insert a small paper ball(but still big enough to be kind of hard to get out, this is what determines power) and push it all the way.

Squibb (author)2011-04-22

Next time, you should try to make a semi-automatic mechanical pencil gun. Just drill a hole in the barrel of one pencil and then stick the other pencil in the hole. Fill it with BBs or whatever you want that will fire.

Jeuan (author)Squibb2012-04-08

The bb's jam I tried it a while ago, they end up going half way in the barrel with the one you're away to shoot

Vanila (author)2012-02-20

You can also use these at close rang by pulling back and "popping" someone with gray part that protrudes from the end of the barrel.....In elementary school I took one to school with intent of shooting various objects. However by the end of the week the favor was returned with a painful "pop" by a weapon now dubbed the "popper" by the sound it made when you "popped" some. (Within days every guy had one)

jaylan77 (author)2011-11-09

try using choped up secsions of a pencil?

meatygut (author)2008-07-30

i did but it doesn't hurt or anything, do u have to use bb's? cuz im using things like pebblez, dog kibbles and bird food, but nothing work

hoogilyboogily (author)meatygut2008-08-13

hey wat r bb's?

jbyrd117 (author)hoogilyboogily2011-10-02

butterfinger bb's

Ball Bearings

Air_Assassin (author)runtherd992010-12-18

No they are ball bullets

Air_Assassin (author)runtherd992010-12-18

No they are ball bullets

DacrazyDude (author)runtherd992010-11-28

ball bearings are too heavy to fire out of a pencil gun. i think bbs refers to the kind that are shot out of an airsoft gun

175airsoft (author)meatygut2010-03-17

Use little knex pieces i made one and that works best Once i was in class and i accidently shot my teacher but no one admitted it .

cookie38 (author)175airsoft2011-03-14

Epic dude i wont forget u .u r my idol will you be my friend

letnetik (author)meatygut2010-10-29

I used small cut up skewers cut off the grayish part that sticks out, loaded the pieces into the grayish part of the pencil works perfectly!

dirtnap (author)meatygut2009-12-10

Wow man. Dont use bb's. What you do is get a piece of paper and wad it up to the size that fits your barrel then staple one end of it, and make the staple pointy so it can hit the victim and go into em'.

fastcalvin (author)2011-10-01

i love this thank you very much

samaside (author)2011-04-25

Anyone know what size BBs work the best?

knexdestroyer (author)samaside2011-09-07

6mm .12 g bb's would work the best

kylekosan23 (author)samaside2011-08-03

regular airsoft bebes

kylel (author)2007-01-20

Hey thanks this worked great for me!Got any ideas for some ammo?My tubes slightly bigger and it shoots airsoft bbs.But i cant think of anything else

ruiqim (author)kylel2008-06-16

Try blowgun darts (trim them) or wadded up pieces of paper. They actually hurt!

tperrette (author)ruiqim2011-01-26

of course blowdarts would hurt...

samwhiteUK (author)tperrette2011-07-08


175airsoft (author)kylel2010-03-17

Knex hurts like heck if you pull it back really far

foxtrot4697 (author)kylel2008-07-26

folded staples sting(open 1 side, it can pierce skin!put the closed side in the barrel)

oa-j (author)2011-04-21

just use the pen ink cartridges... works fine but curves alot.....use close range

cwestrum (author)2011-03-18

you can put staples or needles in the wax too.

cwestrum (author)2011-03-18

I like to use a little bit of wax candle or cheese wax. It sticks to the black end and you can stuff it so it compresses the air and hits harder.

sszeprocks (author)2007-01-09

dude, how much fps is this thing

cookie38 (author)sszeprocks2011-03-14

6000000 mile per millisecound

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