25MM Pneumatic Sniper Rifle

Step 7 Trigger assemlby

the trigger assembly consists of only a few parts but ti requires heavy modification. the first step is modifying a short 4 inch long piece of 3/4" pipe. you need to cut two slots in it length wise so a blow gun valve can be inserted into it. it is rather hard to describe so just look at the pictures. the next part is the 3/4" 45 degree elbow, you need to make a hole in it so you can connect a hose to the blow gun. once again refer to the pictures of this piece also but before you cut the hole remember to glue in a short piece of PVC into th elbow. after the pieces have been modified connect the elbow up to the rest of the gun (using the 90 degree 1" elbow that was modified earlier) and hold in in place with a screw of some sorts (so the trigger doesn't twist to the side as your firing). once the elbow is secured on the gun feed the hose through the hole in it and connect up the blow gun valve. then your pretty much done, congratulation's you have a 25MM sniper capable of doing some serious damage

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Comments

[blubberdubber]

Where can I get all the materials needed for this in the UK? I can't find PVC in particular.

[jaddis2]

what part

[jaddis2]

hello love the gun just wanted to know on the video what did you use to put the air in the gun what your friend used p,ease please could you tell me

[sanjukchandran]

hi frnd.its amazing one. u hav a brillient future.i apriciate u.gud luck.

[Dienerone]

hey dude, i started making this gun yesterday, and all i have really left to do is attatch the stock, attatch the handle and wait for the pvc cement to dry, cheers mate, helped me heaps........great tutorial.

[fernandojuanjaimearturo]

100psi ???? nooo or....

[wolfgun]

I LOVE THIS GUN I MADE!!

[poosh507]

COOL!!!!!!!

[tepetty4]

you have to use what ever the sprinkler valve is rated to

[polabearboi]

whats the best way to modify that 3/4" piece of pipe?

[bombmaker2]

I used a scrollsaw for most of the cutting then when one slot got longer, I dremeled the rest out.

[wewantska]

anybody know how to put the hose on the blowgun valve pls reply as fast as you can

[GhostSade]

Since the blowguns I've seen are all 1/4" on the top, get a 1/4" hose barb, screw it in there, with teflon tape if you want, then slide braided hose over it and push down hard until it's all the way down. Instead of using compression fittings, I just used a 1/4" hose clamp and slid it down all the way on the pipe. I then used epoxy all over that and, after the epoxy dried, slathered a bunch of epoxy putty onto that, for a definite airtight seal. Did that with basically every air fitting on this, espiecially the modded sprinkler valve. I also used a ball valve in between the sprinkler valve and the blowgun as a safety.

[audio8448]

 i used the same kind of sprinkler valve mod with the tubing going to the blow gun for an air cannon i built. my air cannon can also run off 12gram co2 cartridges but i think when i break the cartridge open the sprinkler valve lets a bit of the gas out. i think this happens because of the tube in between the blow valve and sprinkler valve allows pressure to be released from  the sprinkler valve opening it all the way for like a fraction of a second. i think when you use an air compressor that doesn't happen because the air enters more slowly instead of all at once. does that make sense? do you know how i could stop that?

[yourworstnightmare]

how do you fire it could you add another step explaining how to fire it

[dan5jr]

This project is fairly complex if you have little or no experience.  It also can be very dangerous without the proper knowledge.  All of your questions can be answered by reading the tutorial more carefully, looking at all the pictures, and researching the basics behind pneumatic cannons.

If you are trying to quickly 'throw this together' for a science fair, it's probably not such a good idea.  If you are interested in building one for yourself, start by reading all of the related instructables you can find as well as by using Google to help answer specific questions you may be having about individual components.

For some quick answers to your questions: 1. Expect to spend around $100 if you are starting completely from scratch.  2.  The air is pumped into the chamber through the quick disconnect valve using a hand pump, compressor, etc.  3. Your "ammo" is loaded into the barrel through the bolt, the gun is then pressurized, and then the blow gun trigger is pulled, opening the valve and releasing air, which in turn will launch your projectile.

[bombmaker2]

is the $100 in US dollars because I started this project completely from scratch and only spent about $30-$40, including the sprinkler valve

[dan5jr]

Yes, that's $100 US. I guess it depends what you mean completely from scratch.  Here's how much everything loosely cost:

Sprinkler Valve ~ $20 (bought online, you probably can get it cheaper)
Blowgun ~ $6
PVC Cement + Primer ~ $10
Tire Valve (2 pack) ~ $5 (probably could find one for free)
Plastic 7min Epoxy ~ $10
PVC Pipe ~ $15
PVC Fittings ~ $15 - $20

All that adds up to a little over $80.  I also got the pressurized air line and fittings for free so I'm not sure how much that would cost (didn't have pressurized tubing at home depot, surprisingly).  I also still need to purchase a scope and a pump which will definitely set this project upwards of $100.  I'm sure you may have some of the items lying around, and can definitely get some cheaper than I did; but if you really are starting from scratch, i don't see how you could spend only $30 - $40.

On top of this, I have a ton of tools at home and have access to a machine shop.  You need to make sure you have the proper equipment and tools to complete everything before you start spending money on parts.

[bombmaker2]

I had the blowgun, the epoxy, the pvc cement/primer, and tire valve. The pvc pipe and fittings are way cheaper than you say. that cost me about $20 total. Then the sprinkler valve cost about $13.

[yourworstnightmare]

 thanks the budjet is 140$.i knew that you pump the air in with a pump/compressor. i also know that ammo is loaded in through the bolt , the blow  gun trigger releases the air which launches the projectile

[neonflame7]

me lives in jamaica although down here we dont got much stuffz....gunnamake this on saturday.....wish me luck.........................P.S. JAMAICANS DONT SAY "MON"

[spaztec]

 YA MON.

[yourworstnightmare]

 hi

[CHUBSY]

Hey

irwinner

i wanted to ask if you can sell me one because i have tryed to do i 3 times and its all a big fail. I know its not your instructions because i follow them step by step but some how it never comes out. if you can sell me one reply to this Email- [e-mail]- how about it ill pay the shipping and you put a reasonable price in US Dollars

[bunkatron]

what can i use for bullets

[DinerKid]

so is there anything to stop the blow gun from sliding out of the slit piece of 3/4" pvc?

[belikozo]

blow gun cost $ 6

[knifepyro]

were can i get the blow gun valve and how much does it cost?

[Willard2.0]

You can get the blow gun at just about any hardware store. It should be about $6-7. Here is a link to a harbor freight one http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=3962

[thatfamousguy]

just made one, I use it as an "pneumatic speargun" incase anyone asks. I just shot some rolled up newspaper with tape around it. blew a hole in an old unused plastic dog house. the trigger mechanism was a bit tricky to understand, but i made my own version. would like to know if i can mod it to shoot tiny plastic pellets about 3-4.. dia that i have a whole bag of

[bobt4]

plz dont fire tooth picks........it impales

[mikevanky]

cool, I want to use it as a speargun as well... could you give a general description of your ammo and how your line is attached to the end of the spear?

[thatfamousguy]

nah i dont really use it as a speargun, just thought i may be able to pass it off as one, or a water bubbler (lol) for my fish tank if i get caught with it. trying to make it shoot smaller bb size plastic pellets.

[kyle7119]

Here is the link to the video that the author of this article made.
http://www.youtube.com/watch?v=5D-_e26Vv5o

[uzairsagitarian]

HELP! HELP! HELP! HELP! QUESTION: I have found in my local market (PAKISTAN) the pipes with following ratings (PVC 1" SCH 40 PSI 450 ASTM D-1785) and (PVC 2" SCH 40 PSI 280 ASTM D-1785) Does that mean that they have pressure ratings of 450 and 280 PSI respectively? Help would be really appreciated

[jm838]

Yes, it does, but you should never fill it anywhere close to that, as it is not designed for use with air. I have heard that it is safe to fill it to half the pressure rating when using air, but just be careful, theres always a chance it could explode and sverely injure/kill you, especially if you didn't put the safety pop-off thing on it. If anything happens, I take no responsibility...

[Thelonelysandwitch]

You're right, one of my dads friends had a piece of pvc blow up on him. He didn't realise that the compressor filled up that fast.

[uzairsagitarian]

Thnx Dude I was gonna fill it to a maximum of 100 psi anyways

[R1Ch0]

consult google, it knows all

[Montsombre]

the picture are so self explanitory that you barley need the instructions does anyone agree