DIY Airsoft Cap-gun





Introduction: DIY Airsoft Cap-gun

This will show you how to make a cheap airsoft gun out of a cap gun. This is not to be relied on in an actual airsoft battle. It's just a fun project to try.
Please Rate!!
7-31-09: Today I found that 12hippos posted the same project as me, but about 6 months earlier. Please note that I did not copy him, as I did not know the instructable existed. If you really want to see heres the link.

Step 1: Get Your Supplies

You will need a cap gun revolver. I got this one at Albertsons for 2 bucks
You also need caps. I got a pack of 24 cap rings for a buck at Albertsons
You need airsoft bb's (of course). You can get these at wal-mart or any sporting goods store.

Step 2: Widen the Barrel

Use a knife or a pair of scissors to widen the barrel so a bb can pass through. Make sure it's wide enough by dropping a bb into it. The bb should pass right through.

Step 3: Insert the BB's

The gun I have has a removable cylinder, which makes it easier to put in the bb's. Check the picture to see where to insert the BB's. After you have put the bb's in, you need to push them down as far as they will go. I used a screwdriver.

Step 4: Reassemble the Gun

Put the cylinder back in (if you removed it) and put the cap ring in,

Step 5: Use Your New Airsoft Gun!

Your airsoft capgun is now ready to fire. Always use eye protection when firing the gun, the bb's are prone to ricochet.

Step 6: Improving Accuracy(optional)

I managed to increase the accuracy of the gun by hot gluing part of a pen tube to the barrel. Another section of the pen tube is placed inside the gun, as seen in the picture.



    • Water Contest

      Water Contest
    • Backpack Challenge

      Backpack Challenge
    • Oil Contest

      Oil Contest

    107 Discussions

    This is a firearm.

    "any weapon (including a starter gun) which will or is designed to or may readily be converted to expel a projectile by the action of any explosive;"
    -18 USC 921

    The projectile that is expelled is the .12g plastic BB, the explosive is the cap.

    Its not illegal (unless you love in NY or Cali, or IL w/o a foid card) but you need to be over 18 to even possess it.

    All firearm rules apply to this.

    In some states, the construction of this w/o a gunsmithing license is a felony, and ill land you in jail for more than 5 years, and remove your right to vote, own a firearm, etc.

    4 replies
    via ATF's Q&A sectionDoes an individual need a license to make a firearm for personal use?

    No, a license is not required to make a firearm solely for personal use. However, a license is required to manufacture firearms for sale or distribution. The law prohibits a person from assembling a non–sporting semiautomatic rifle or shotgun from 10 or more imported parts, as well as firearms that cannot be detected by metal detectors or x–ray machines. In addition, the making of an NFA firearm requires a tax payment and advance approval by ATF.

    [18 U.S.C. 922(o), (p) and (r); 26 U.S.C. 5822; 27 CFR 478.39, 479.62 and 479.105]

    I'm just merely interested, what if someone in Canada was to do this?

    Buy liberal amounts of KY Jelly for your going to prison bag. Although here in Australia some Prisons will Issue you with Rubbers and water Based Lube, When asked by your cellmate if you wish to play " Mummies and Daddy's " ALWAYS ask to be Daddy. However most of the time in these situations Mummy will be a Pre - Op Trannie.

    Sorry couldn't help myself, seriously though, most countries in the Commonwealth mere possession, will almost certainly attract stiff penalties. Manufacturing will certainly get you in the deep end. I believe Australia and Canada have similar Gun Control Laws. Here in Australia you can expect SERIOUS Jail Time, and Deportation if your not a Citizen.

    I'm just merely interested, what if someone in Canada was to do this?


    11 months ago


    How hard will this launch the BBs? My experience with plastic ring cap guns is limited. I'm curious as to how much gas they will produce.

    13 replies

    I managed to dent an aluminum can from about 15 feet. It packs a pretty good punch, and only hurts as much as a regular airsoft gun. The tricky part is aiming, because this thing is pretty inaccurate.

    Well, adding the pen tube is the only way to make it more accurate that I have tried. Also, I use 6mm bb's .12 grams. The biggest problem is that the gun itself is extremely low quality. Mine is starting to fall apart, and I've only fired about 50 bb's. The fact is, this is just a cool project to try with your old capguns, not a reliable weapon to go airsoft with.

    there would be another way for improving aiming: just add 2 BBs instead of 1, so you have something like a small shotgun. i didn't try, but i think it could work

    To much weight, friction, and resistance. Remember it's a novelty project not a real gun so don't expect that kind of performance, as that is just a plain silly expectation.

    However if you were to paint it black or silver and a cop see's/hears you fire it expect to be shot when you turn around, unless you drop it and raise your hands palms open before turning to face a LEO, from his perspective it went BANG and there was a Muzzle Flash remember the poor guy only has SECONDS to react.

    LOL! Still, pretty cool. Is it still as inaccurate with the pen casing inserted? I would think that would help with the accuracy somewhat.

    if this one goes 15ft, i would say its a very-short-range secondary/sidearm, so i think its ok if its not so accurate.

    I used to own a .32 Calibre S&W snub nose from 5 feet it only dented a fairly lightweight 44 Gallon drum. it's the Nature of a snub nose.

    You will find the same problem with a REAL snub nose, thats why they are nick named " Gut Busters " as they are generally a close quarters weapon and often pressed hard against the assailant.