25MM Pneumatic Sniper Rifle

***Disclaimer*** The following is for informational purposes only, i take no responsibility for what you do with this knowledge. i can not be held responsible for any property or medical damages caused by this weapon. i would advise you to check your local laws. These types of guns are illegal in some areas, and i would highly advise you against building one of these in said areas. Pneumatic rifles can be very powerful and should never be pointed at a person or animal. Lastly when dealing with pneumatics never over pressurize them and always use NFS-PW pipe (as apposed to DWV)

well before we begin i must state a few things...

-PVC can only be used at half or less than half the pressure rating stamped on the pipe when pressurized gases are used in the pipe
-i would suggest never pressurizing this cannon above 150 psi, remember its only plastic
-never store any type of PVC pneumatic with pressure still in it
-always allow a full 24hours for PVC glue to dry before pressurizing
-when building pneumatics always use metal or PVC pipe (never ABS)
-PVC is shock sensitive meaning if its dropped on a hard its very likely it will be damaged and it would be very dangerous to pressurize after damaged
-PVC becomes very brittle below 32 degrees (Fahrenheit) and is very likely to explode if pressured in such conditions
-when building pneumatics pressure rated pipe should always be used (none of that cell core or DWV crap)
-the most important part of any pneumatic are the PVC welds AND I HIGHLY SUGGEST YOU READ THIS TUTORIAL before you even think about starting this.
-when you are dealing with high velocity projectiles always remember you safety glasses
-always be sure of your back stop when shooting any form of rifle, pistol, gun, bow.... anything that can fire some vague form of projectile
-and use common sense!
-do not use un-regulated HPA or CO2 in a PVC cannon ever they are stored at to high of pressures to be safe in PVC, but if you have a properly regulated setup they can be used ( if you lower the pressure to about 100psi)

Now onto the good part...

this is my entry for the launch it challenge, it is a 25MM Pneumatic Cannon. it has 2.5 foot long one inch diameter barrel with a custom bolt action mechinism, of course we have the 3-9X40 sniper scope, and a 1" modified sprinkler valve as the primary firing valve.

The Video...

Video

invalid movie: http://youtube.com

remember always wear safety goggles, you never know where or when something will ricochet especially when its traveling at 300+FPS

Fun Fact: PVC shards can't be picked up by X-Rays (this is a safety tip! don't rush or you'll get a PVC shard in you and you probably wont get it out. im not saying you should sneak one of these into your luggage and go threw airport security. it would be way to big any way)

better video coming soon

If you like this instructable please register and vote for it in the launch it challenge (by click the plus icon next to the title)

DETAILED SPECS

power source------------------compressed air
power source pressure-----100psi
chamber volume--------------45 ci (approx.)
barrel volume------------------25 ci (approx.)
c/b ratio--------------------------1.8 to 1(approx.)
firing valve----------------------pneumatically actuated sprinkler valve (a "modded sprinkler" valve)
pilot valve-----------------------blow gun valve
fill valve--------------------------female quick disconnect
fire rate--------------------------single shot, bolt action
caliber---------------------------25MM ( one inch)
projectile velocity-------------unknown (coming soon)
effective range----------------unknown (coming soon)
maximum range-------------unknown (coming soon)
optics---------------------------3-9X40MM rifle scope
primary material used------PVC pipe

I WOULD SUGGEST YOU DO SOME RESEARCH BEFORE UNDER TAKING THIS PROJECT, LOOK INTO THE DIFFERENT TYPES OF PIPE AND THERE RATINGS, HOW TO SOLVENT WELD PVC (THIS IS A MUST), HOW TO PROPERLY DRILL AND THREAD HOLES FOR FITTINGS, THE TYPE OF CONDITIONS PVC CAN BE USED AND STORED IN. THE MAJORITY OF THIS INFORMATION IS CONTAINED WITHIN THIS INSTRUCTABLE BUT IT IS BECOMING CLEAR THAT MANY OF YOU ARE NOT READING ALL OF IT. I HAVE ONE FINAL SUGGESTION BUILT A BASIC PNEUMATIC OR COMBUSTION FIRST IF A BASIC CANNON FAILS IT WILL BE LESS DANGEROUS

PS - DON'T ATTEMPT THIS AT ALL IF YOU HAVE NO COMMON SENSE OR A LOW IQ

Step 1: The Parts...

we will be making this particular pneumatic out of mostly PVC so it is relatively inexpensive to make. here is what your going to need.

Parts...

( 1x ) 2" PVC cap
( 1x ) 2" PVC coupling
( 1x ) 2" to 1" PVC bushing
( 2x ) 1.5" PVC couplings
( 2x ) 1.5" to 1" PVC bushings
( 1x ) 1" PVC tee
( 2x ) 1" PVC 90 degree elbows
( 2x ) 1" PVC male threaded adapters
( 1x ) 1" to .75" bushing
( 1x ) .75" PVC cap
( 1x ) .75" PVC tee
( 3x ) .75" PVC 45 degree elbows
( 2x ) .75" PVC 90 degree elbows
( 1x ) female quick disconnect 1/4"
( 2x ) 3/8" by 1/4" compression fittings
( 1x ) blowgun valve
( 1x ) 1" sprinkler vlave
a few inches of 1/4" ID flexible tubbing
assorted bits of 2", 1.5", 1", and .75" pipe

Tools...

a dremel
a band saw
a drill (preferably a drill press)
PVC primer (make sure its primer and not cleaner or it could end badly)
PVC glue

Comments

[jaykay007]

About to make this model, Upload images after its completion

[MadBomber12]

This is ganna sound stupid, but what's the best ammo for this rifle?

[hanelyp]

I'm thinking marshmallows would work well.

[Denasdc]

And also: Why do u need coupling in the bolt action?

[Denasdc]

Hello all. I'm planning to build this one with few little changes to it. But i have only one problem considering this: When the bolt action is set up: the barrel itself will move up, or it will stay and the other piece with same diameter will move to the barrel? I just can't get it. Will you help me this?

[cade nielson]

i im thinking of making this about how much did it cost you?

[MakarovII]

This is a good airgun what is the projectile of this stuff reply me cause i made one and i appreciate your work good job...

[hunter1125]

So if you pressurize the tank to 100 psi does it shoot well, and does tank size have a factor besides amount of shots?

[mamajr96]

Couple questions, do you have to use an air compressor to fill the tank each time can't you mount and second tank filled with air and leak it into the other tank to re-fil the main tank. This is a dumb one but I'm guessing you have to re-fill the tank each show right

[batonas]

(removed by author or community request)

[jumpup_dnb_dj]

The term 'rifle' is not meant to be taken in the literal sense. The term 'rifle' has been used to describe a variety of weapons that use a stock and is to be shouldered before one fires it.

This is a fun instructable and I don't believe the accuracy of what you speak of here is required.

So the owner of this instructables use of the term of 'rifle' is more than acceptable.

[Zach the Man]

and is it only one shot?

[Zach the Man]

i think my jaw just fell off my face when i saw that thing

[fjdutra]

Well, to get where I find this valve and how it would be worth it if I send him the money and buy a pro Brazil send me inside mines can give me an answer on my imail [e-mail] required urgent thank you for comprehension


Fabio Junio ​​Dutra

[lewster]

This is incredible! Have u thought about using paintballs or splatballs (from kmart) and a 15mm barrel to shoot them? This could be used with a spring feed, or just bolt action, for an incredibly awesome paintball gun! i have another air cannon (i lie, i have 3) and splatballs work great! u get them from kmart, or maybe walmart if ur in America?

[dog digger]

In america, you can get proper paintballs anyway

[lewster]

I KNEW THAT!

[lolzprox]

Hey anyone know where to get that sprinkler valve? And the blowgun valve.. I live in Singapore, which none of the DIY stores sell such stuff. And any idea if i can replace the sprinkler valve with ball valve?? Thanks.

[de0509]

haha hello there, im from your neighbouring country. yeah, ball valves work fine too if we cant find those QEV stuff. mine uses a ball valve too. its less complicated but it still is fun.
but judging from the date of your comment, i guess you may have already made one diy airgun for yourself....

[dog digger]

A ball valve will work fine. You just have to open it faster :)

[deqwer]

is there any chance that the air gun can shoot twice?

[de0509]

i dont think it can be done with just one valve.

[popcannon]

this may be a thick comment but where can i get the sprinkler valve and is "sprinkler valve" its real name?

[monkhm]

Check out spudtech.com, they are expensive but do the hard work for you

[acaz93]

it is the actual name, in fact, you can find them in many stores as "solenoid valves".

You can find them in several home improvement stores and wherever they sell irrigation products.

[jfsimalesg]

RIFLE FOR PORTIONS OF THAT HAPPENS THE AIR ??????????????

[ltran7]

I can't find 1" anywhere what can I do??

[fr05ty911]

instead of gluing the chamber in could you use a quick disconnect so you wouldn't have to keep refilling it and just swap chambers???

[djzadjza]

thats a god idea but the disconnect might be two small so you would have to use some reducers.
but that would be a very good idea if you were using the gun away from an aircompressor... infact i might try that

[popcannon]

maybe u could hav a hwhole second tank with a female disconect at one end and a male discnnect at the other, so u could fill it at the commpresser and then when u wanted to use the cannon away from the commpresser u could fill from that

[deobomb]

yeah you could make it snap on and off to make a fast change air tank

[shaclonts]

Wouldn't that not work because the whole idea of the compression chamber is to quickly release the air? If you could do it that way you might as well keep it attached to the compressor and forgo making the compression chamber altogether.

[Syn7]

or use a real tank and have multiple shots. It's not the same. The whole concept here is a complete release in one shot. Hooking it to a direct infinite source requires a slightly different design. There are lots on here, just search.

[Syn7]

Although, you could just carry a pressurized tank with a scrader valve filler attachment and use that to refill your pvc canister while in the field. Prolly a good idea to have a guage handy if you don't have one built in with the valve.

[stevenh429]

Does it matter if your blow gun is rated at like 90 psi and you want to shoot at 100+?

[penguinparty123]

this would be better if it had a trigger

[deobomb]

would it work to just run air hose from the tank to the triger and from there to the back of the barrel instead of useing the valve?

[mrfuzz]

When you fire the gun won't the compressed air just leek out of the breech loader?

[irwinner]

it does but only a little, not to the point where it effects performance much

[Country dude]

couldn't you improve the preformance by sanding down the end of the barrel smooth (the end inside the bolt), then were the barrel meats the back of the bolt assembly you could put an O ring in there. in tern would stop a fair bit of air from coming out