DIY Airgun - Bull-pup 

I'm also have one these with the same system that i built myself..but yours its much simple,compact and looks professional,I like it,you give some inspired to me to improve my airgun..thanks back to you..

I see what you mean! Makes sense to use a rotating valve - something like a hole drilled through the thread of a bolt/screw. I do like the idea of a screw to loosen or tighten the hammerspring, like paintball gun. Thank you very much for the help!! Have given me a few ideas!

And this is what the mainstream airgun manufacturing companies copied this design from!😮 Damn great job! 👍👍👍👍👍

i love how skelotonized and simple it looks

you are one clever guy, really enjoyed watching your vids

Damn, I must be getting old. Remember when this video was only a month old!

@taself09 Thanks! The valve is a simple knock open valve, think of it as a valve in a IC engine, the striker hits the valvestem, the valve head lifts from the valve seat for a fraction of a second, air is released.. The valve closing force is provided by the high pressurized air in the bottle, 200Bar is a pretty good valve spring! Cheers

Ez nagyon állat légpuska! Gratula!!

Thanks! Please be aware that airgun building is highly addictive... once you get hooked there is no way back! Don't forget to show your project once you get started. Cheers

Really nice work dude. you should be proud

Lol! You are closer to the truth than you might think... i have settled a deal with the missus..; as long as i take care of the laundry, i don't have to do any cleaning whatsoever (except for my workshop that is...). Cheers!

Thank you for the kind words! Some airguns are fitted with a small "jet" sitting between the valve and the barrel, if that is the case you can just swap it for one with a bigger diam transfer port hole in it.. Otherwise you can use a type of "crossbolt system" through the receiver..; turning the bolt means blocking/unblocking part of the transfer port.. Or maybe use a simple screw to adjust hammerspring tension. Space is limited here, can't explain it better... out of letters! thanks

@Kereyuli lol wrong reference. he's referenceing the bull-pup style of gun building, where the bolt, action, and magazine are all located behind the grip/barrel,and are generally built into the stock of the gun, allowing a shorter overall length of the firearm while allowing a longer barrel than one would expect. it's a more space-efficient gun design.

i fully understand it. i came up with the same concept for my gun before i read this :)

You are perfectly right! very simple knock-open valve.. thanks

Not at all Brother , hope all with be Fine and sorry to hear about your family thing , i know your busy with your life so any time u can :) i have all the time in the world , Thanks and wish you all the best .

nice device, looks like a lot of work put into it.

Hey man.....this is pretty freakin sweet i have an old airgun barrel lying around i feel inspired :3 cool man I like it 5 stars

Nice work but the only thing that worried me slightly is having my face right next to the breech. A simple flip over cover for the breech would offer some rudimentary protection to the face. Other than that, brilliant.

Hi Pop, this is actually my own design, but the mechanism is veeery much inspired by Mr Buckleys books that you mention. Lets say it's a mix of the blueprints from both of the books. Once you get a basic understanding of the working parts of a PCP airgun, it's easy to alter the design and build a gun that looks just the way you want it to. Cheers

some very nice work.

Thanks! I have now finally got around to make new stock for this gun, and add som blueing to the barrel and bolt. Hopefully I'll have time this weekend to shoot a video of it. Cheers

I wish I had that sort of skill...

@vwrFEW thanks for showing interest in my projects! Just like you said; there are no blueprints for this specific gun, but all my guns are very much based on Mr HM Buckleys designs. Mr Buckley has written two books on air gun building, complete with blueprints. Excellent books! Please don't ask me for blueprints; i won't sell out someone elses work.. Mr Buckley has put an enormous amount of work into writing those books, so i think he is worth every £ he can make from selling them. cheers

TAK, my apologies for not replying to your previous comment regarding the working parts of a co2 rifle.... Anyway, the thing is that I'm going through some family problems, and my spare time is just non existant at the moment. Hopefully things will get better, but at the moment I cant say when.. thanks

@BritishSoccerNut the valve is a simple knock open valve, turned from brass rod and a piece of delrin. Built it useing my bench lathe. cheers

This is one of the baddest DIY guns Ive seen. Im new to this can you tell how it keeps from dumping all the air at once. I want one of these keep up the good work if you build another I would buy it.

I use an FX airgun pump.. A good workout to fill a bottle from empty!

you can get 200 bar by charghing a scuba tank or co2 welding tank and then transfer the co2 or air but this involves money to spend. but you can get easyly 40 bar from a fridge compressor or 60 bar from a air conditioned compressor external unit.( i have one but it pushes the air up too fast and heat up my air tank. just a little to explode)

@ulanbatorgator Hi! Great result on your rifle - incredible machine work! I was wondering if you may know how to regulate power output without cutting or replacing the return spring in the valve or on the striker? Like a variable power valve?

looks like a hacksaw...very impressive build though, thumbed up

@pyronathanpyro Thanks for your comment. What you need to build is a simple knock open valve, a striker mechanism to knock the valve open when you pull the trigger, and a bolt action to seal the breech end of the barrel. A typical PCP gun valve is held closed by the pressure of the HPA (or C02 in your case..) To aid in closing the valve you can fit a small return spring. When you pull the trigger the striker hits the valve stem, opens the valve for a fraction of a second. out of letters now!

not at all , I'm working on my Motorized Air Rifle and i know shit is Ain't Easy :) , nice work , wish you the best .

Thank you very much for the kind offer! I did however finally build a stock for this gun..., I Think i posted a clip with the new stock also here on youtube. Anyway, thanks again and best regards /O

that thing is awesome.

@XXhizzors Thanks mate! I might not need it... but building stuff has become an obsession.. Cheers

Thanks! I ended up making a manual indexing 15-shot mag on this one.. I think the mag is shown in one of my other vids.

@DragonRoLo Thanks for the input! I totally agree.. Hard to tell from my blurry video i guess, but what you are looking at is a 280cc, 232Bar air bottle.. I have never tried C02, air is cheaper! thanks

Can't wait to see it! Cheers

@erwiney hi, hmmm.. don't know actually.. maybe if i had enough time! The thing is is that i don't really see the need for a fully automatic gun. Maybe i'm old fashioned, but i would always choose an accurate single shot over a not so accurate auto. thanks

Thanks for your comment! The bottle is called a "buddy bottle", comes in different sizes, most common sizes are (at least over here..) 280cc, 400cc or 500cc. There are a lot of paint ball bottles ( air bottles..) that also can be used. Cheers

awesome air rifle, one of the better!

Hi thanks for the kind words! This one is my own design... built around a mechanism designed by Mr HM Buckley. There are no blueprints available for this specific design, but if you get hold of Mr Buckleys book "The modern Pneumatic airgun" you'll have a wounderful step by step guide to building your own airgun! Look for the website "airgun development", it has links to Mr Buckley. Good luck!

@ulanbatorgator thanks alot man you realy helped me...nice gun btw :)

great vid but i was wondering if you could make a vid or tell me about the valve and how you made it

thanks for your comment! the noise is due to my camcorder...; bought it back in 2001 when me and my gf were backpacking in oz and nz.. This camcorder has had a hard life, but still refuses to die.. thanks

@furyjeff76 This one is a "diy-gun"... which in my case means that i buy a barrel, pressure vessel, o-rings, a few springs and screws. The rest is cut from stock. thanks

@27simber The airbottle for this gun is made by a company named "Luxfer", they make a lot of different pressure vessels. thanks

@27simber Hi, I use a simple stirrup pump to fill it... just un-screw the bottle from the gun, hook it up with the pump, fill to 230Bar.., put it back on the gun. The bottle is fitted with a schrader style valve so the bottle can be removed from the gun no pressure lost. thanks for watching!

@ulanbatorgator ahh thanks so much i was kinda lost you see would something like a hammer valve work and the add a small bolt and lock with a spring behind it so when i pull trigger it releses flys forward and hits open the hammer valve leting air out the valve then the valves own spring sends the valve and bolt back closed and all i do id re engage the bolt and stick a new pellet in the breach oh and the breach will be most like the one on the site with a small bolt acton and a 0 ring thxxx

i think so, i mean if you make a good airgun like that,you have a good barrel too

Cooool! You made your own airgun! Wow! 5!

Hey, I'm a really big fan of your bullpup. The craftsman ship is just phenomenal! I was just curious as to wonder if you would do a custom bullpup rifle?

Thanks!

Yes, very much so! Thanks

Really nice gun you have there...can u make a video how do you assemble that gun. Thanks

I just read your post useing "google translate"...; thank you for the kind words! best regards

nice rifle:) good job :)

@nilsie12 Thanks for watching, and good luck with your projects! Cheers

woow man thats so awesome :) im going to make one just like yours il post a video :)

how to videos are the best ; )

@carbonrocket Thanks! Feels good to hear that from you. Somehow the "airgunning world" seems very small and i sometimes get the feeling that i know the persons just because i regularly watch them on youtube... Anyway, are there any upcoming airgun events in the UK that you consider worth visiting? A lot of cheap flight tickets around you know.. thanks

@bayenne5b Just like all airguns it's rather wind sensitive, but the reason for shooting indoors is that i don't want to upset my neighbors! thanks

@ulanbatorgator lol i never asked for plans, i already know how this works without even reading the book. its just a simple hammer valve or knocker valve as some call it. very simple yet efective design.

The pressure in airtube provides a closing force to the valve that can be described as pressue/surface area x surface area of valve. When the striker hits the valvestem the valve opens for a fraction of a second and releases air.. once the striker has lost it's momentum the high pressure in the air tube slams the valve shut again. Is that possible to understand? A bit short of space here to give a better explanation. Thanks

Hi this video is a real inspiration to me to build a air gun of my own air gun. But in the process of designing it i ran into a problem. This being the fact of getting the co2 up to the bolt and .177 caliber pellet. If you are willing to tell me how you did it that would be great. Thanks. By the way i love the craftsmenship and bullpup design. I subscribed. FIVE STARS

@guykr10 Hi, the airbottle is taken from an old theoben rifle... It's a 280cc item, made by Luxfer. thanks

cool vid,if it was my gun i wouldnt be worried about a decent looking stock,the lighter the better dont u think?

How much muzzel energy / velocity does this give?

If I had wanted a Gamo I would have bought one. I prefer PCP guns over spring or gas ram powered air guns. To each his own,, Cheers

By googling stirrup pump, and 3 stage stirrup pump you will find exploded diagrams of hand pumps that do just that. =)

man if only companies made guns like that to sell.... instead of paying 100s of dollars for looks :(

haha thats some nice shooting man

@ulanbatorgator Oh, ok. Btw. nice made! What about the velocity?

Hi there! First of all..; sorry for not replying to your previous comments and question! The pressure vessel on this gun is a 280cc bottle, rated max fill pressure is 232Bar, don't know the weight, but I'll look that up for you later tonight. Cheers

I love this. Did you buy an off-the-shelf rifled barrel?

Awesome! how that gun wock ? what happened inside this block where u arm the trigger? is a hammer valve?

Thanks for your comment! Anyway, i do however think that you are more suited to answer that question than I am... Can you get hold of an old scrapped airgun and salvage the barrel? thanks

I like this very very good

Hey ulanbatorgator, nice shooter :) that valve/action/what ever it is, (srry dont know what its called) the silver thing... did you make that? if so, (if its not too much to ask) can you make a video to explain how it works?

Awesome

Hi S, all homemade, except barrel and airbottle...

@EvilGrunt101 Hi, the airbottle is rated max fill pressure 232bar. The trigger on this gun is very basic.. but a bit hard to explain. I'll try to shoot a video of it, but it might take a few days before i get around to it. thanks

Very nice man! Have you seen mine already? 5/5

Can you show me how you made it

Ha ha ha... great gun!!

Hi, thanks to everyone for the input. The stock for this gun is still not finished, but I'm already planning my next project... My biggest problem is to find the time needed for doing stuff like this, but hopefully the stock will be done by the end of october. Cheers

nice work if you need help with the stock, trigger guard and trigger let me know .

You did? was whether this weapon was very good and very smart man you.

@FlYiNgTaCo1000 Yes, pretty much so.. Simple knock-open valve. thanks

Sorry for my bad english :) Ulanbatorgator, which barrel is installed in your rifle? LW? At what energy tuned rifle? Do you plan to participate in competitions, HFT for example? Ans where i can read more about this stuff? PS Nice job, dude!

Nice..God Bless!! :D

if you could give me a name of what the screwing in bottle what holds the air is called i am keen to make an air gun thankyou nice vid

I think this barrel was taken from an old scrapped break barrel gun i had laying around. thanks

Thanks for your comment. I build my own valves.. easily done if you happen to have a lathe. the valve designs i use are described in two of my other videos, they are called something like "DIY air gun valve design" or similar... Cheers

Hi, build cost... i think this one put me back somewhere around 100usd. Barrel is taken from an old airgun i found on fleabay, airbottle secondhand. The few small springs and o-rings needed cost less than 2usd. A part from that you only need , and some raw material such as alu, brass and steel, and some basic machining skills. I'm sure you can build one for even less than 100usd. And yes, the barrel is rifled. Thanks for watching

Hello ulanbatorgator. I was wondering if you could tell me what sort of valve you use and where you buy them? Thanks

i have a question. how do you get regulated amounts of air to leave the bottle, instead of just releasing all the air at once?

Hey can you forward me the part list for making this gun and also indicate how to get better fps and power

you should go and get a 13/3000 psi Air tank the co2 wont give you consistent air pressure and will throw off your accuracy