Login    Register
User Information
Username:
Password:
We are a free and open
community, all are welcome.
Click here to Register
Sponsored
Who is online

In total there are 71 users online :: 4 registered, 0 hidden and 67 guests


Most users ever online was 155 on Mon Aug 15, 2016 1:40 am

Registered users: Bing [Bot], Google [Bot], Google Adsense [Bot], Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

Airgun homebuilding thread

All non-spudgun related discussion goes here such as projects, theories, serious questions, etc. All "off-topic" posts (aka useless posting, determined by moderators) will be removed.
Sponsored 
  • Author
    Message

Airgun homebuilding thread

Unread postAuthor: inonickname » Mon Jan 11, 2010 2:23 am

'Airgun' as in the more traditional type- usually using a hammer valve and in the configuration of a rifle or pistol. Basically, not PVC fittings.

Eg.
Image

I'm thinking with some members now owning machine tools it would be good to create a thread of knowledge to do with home building more professional airguns.

Any resources, information, pictures, diagrams etc. are welcome here. I'll start the ball rolling.

Home building of airguns. Rifling, crosman mods, CNC work etc.
Showcase of modified and homemade airguns, as well as homemade parts
Very nice stocks and homemade guns.

And so on. My computer recently crashed so I lost a lot of my good bookmarks. I have a PDF file with plans for the Caselman AMG if anyone wants it uploaded (or I can find a link with some looking).
  • 0

PimpAssasinG wrote:no im strong but you are a fat gay mother sucker that gets raped by black man for fun
User avatar
inonickname
Lieutenant General
Lieutenant General
 
Posts: 2606
Joined: Sun Dec 07, 2008 3:27 am
Reputation: 0

Re: Airgun homebuilding thread

Unread postAuthor: jackssmirkingrevenge » Mon Jan 11, 2010 2:55 am

inonickname wrote:I have a PDF file with plans for the Caselman AMG if anyone wants it uploaded (or I can find a link with some looking).


It should all be here ;)
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Re: Airgun homebuilding thread

Unread postAuthor: inonickname » Mon Jan 11, 2010 4:42 am

jackssmirkingrevenge wrote:
inonickname wrote:I have a PDF file with plans for the Caselman AMG if anyone wants it uploaded (or I can find a link with some looking).


It should all be here ;)


It isn't. It downloads a 10kb file which is damaged.
  • 0

PimpAssasinG wrote:no im strong but you are a fat gay mother sucker that gets raped by black man for fun
User avatar
inonickname
Lieutenant General
Lieutenant General
 
Posts: 2606
Joined: Sun Dec 07, 2008 3:27 am
Reputation: 0

Unread postAuthor: POLAND_SPUD » Mon Jan 11, 2010 10:45 am

it seems like a good idea... though, I am not a big fan of hammer valves

it would be cool if we could come up with a design of relatively simple to machine high performance valve
  • 0

Children are the future

unless we stop them now
User avatar
POLAND_SPUD
Chief of Staff
Chief of Staff
 
Posts: 5405
Joined: Sat Oct 13, 2007 4:43 pm
Country: Israel (il)
Reputation: 10

Unread postAuthor: D_Hall » Mon Jan 11, 2010 10:58 am

POLAND_SPUD wrote:it would be cool if we could come up with a design of relatively simple to machine high performance valve

I'll see what I can do about getting something on paper (I've had one in my mind for a few years....I just don't have the equipment to build it.).
  • 0

Simulation geek (GGDT / HGDT) and designer of Vera.
User avatar
D_Hall
Donating Member
Donating Member
 
Posts: 1759
Joined: Thu Feb 07, 2008 7:37 pm
Location: SoCal
Reputation: 6

Unread postAuthor: jackssmirkingrevenge » Mon Jan 11, 2010 12:52 pm

POLAND_SPUD wrote:it would be cool if we could come up with a design of relatively simple to machine high performance valve


What's wrong with exhaust valves? Or perfecting the "valveless" detent system...
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: john bunsenburner » Mon Jan 11, 2010 1:15 pm

I say our main problem with this is the fact that we need rifeling in our barrels for pellets, beyond that its pretty simple. Hammer valve or inline piston valve(barrel sealing, DUH) for single shot designs. Pre-charged cartidges( or PCC as i shall call them from now, standign for pneumaticly charged cartridge) would be a great alternative.

Valveless designs are, IMHO the future of this along with PCC when it comes the the discussed cannons especially for semi auto action, i am working on a valveless semi auto design, with a slowly finishing prototype(missing ammo, a few O rings, trigger and chambers).

I say the most important things are barrel making or cheap purchase, alternative valves and maybe stock making.Then there are things like reloading, onboard air supply, and trigger mechs but those can be thought of later, and we have viable ideas for all of those already.

I sense a group project. How about we try design a "normal" gun, perhaps a replica of something people like and if its any good we see who can build it, lets worry about that last.
  • 0

"Did you ever stop to think that out of the seven deadly sins envy is the only one which doesn't give the sinner even momentary pleasure"-George Will
User avatar
john bunsenburner
Major General
Major General
 
Posts: 1446
Joined: Sun Oct 19, 2008 5:13 am
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: POLAND_SPUD » Mon Jan 11, 2010 4:03 pm

exhaust valves
did you mean QEVs and piston valves ? well there are a couple of problem with them...

first of all, their pilot volume is wasted with each shot.. and while this isn't such a big deal at 200 psi (as the volume of wasted air is just a couple of ccm of pilot volume multiplied by pressure in bars) but at 1000 psi and higher pressures it becomes quite wasteful

secondly, you need a pilot valve to pilot them but there are not too many off the shelf valves and other parts rated to HPA pressures... I know that some of you would say that you can always machine your own but it's not always practical

sure I think I could probably use the DCV that I mentioned in one of my posts (the one which has no soft seals) at 700 - 800 psi as well as the QEV.
But that's seems to be the upper limit

That's why I think that it would be a good idea to design a simple to machine high pressure valve.
I've been thinking about this and I think that a valve piloted/operated by regged down low pressure air might be the right solution
  • 0

Children are the future

unless we stop them now
User avatar
POLAND_SPUD
Chief of Staff
Chief of Staff
 
Posts: 5405
Joined: Sat Oct 13, 2007 4:43 pm
Country: Israel (il)
Reputation: 10

Unread postAuthor: psycix » Mon Jan 11, 2010 4:06 pm

You could strip the barrel from a commercial airgun and build your own powerhouse behind it.
2 stage pneumatic anyone? :roll:
  • 0

Till the day I'm dieing, I'll keep them spuddies flying, 'cause I can!

Spudfiles steam group, join!
User avatar
psycix
Donating Member
Donating Member
 
Posts: 3684
Joined: Mon Jun 25, 2007 7:12 am
Location: The Netherlands
Reputation: 0

Unread postAuthor: Demon » Mon Jan 11, 2010 5:31 pm

What would be great would be a detailed drawing of a hammer pcp airgun. As i just got a mini-lathe, i might try to make one.
  • 0

User avatar
Demon
Colonel
Colonel
 
Posts: 743
Joined: Sun Apr 13, 2008 8:46 am
Reputation: 0

Unread postAuthor: POLAND_SPUD » Mon Jan 11, 2010 7:00 pm

Image
that's more less what I am talking about... we just have to design a valve that would offer better performance than a hammer valve and would be cheap to machine... I think that if we spend some time designing this we could come up with something that could be built using only a drill press (and possibly some parts of the piston/spool could be built using a lathe... (or afgan lathe...:wink: if you know what I mean))

the main aluminium block could also house a loading mechanism... or in order to make the gun modular the loading mechanism could be a separate part attached via screws or threads to the valve... in this way the gun could use different calibres and both spherical ammo and cartridges/darts

just think about all the possible advantages - compact construction, low weight, good performance thx to the use of HPA, fully self contained construction

we could turn this concept into a kind of community project... simplicity, low cost and good performance would be the main criteria... then we could create a CAD design of the valve so that everyone could download it and machine one for themselves...

I think that the easiest way to build it is to use a positive pressure piloting piston valve... but I'd like to know what's your opinion?
  • 0

Children are the future

unless we stop them now
User avatar
POLAND_SPUD
Chief of Staff
Chief of Staff
 
Posts: 5405
Joined: Sat Oct 13, 2007 4:43 pm
Country: Israel (il)
Reputation: 10

Unread postAuthor: twizi » Mon Jan 11, 2010 7:55 pm

  • 0

dont play with airsofter with 1000$ gun and play with a 5 dollar pair of glasses
User avatar
twizi
Colonel
Colonel
 
Posts: 511
Joined: Thu Nov 27, 2008 9:04 pm
Location: up yours
Reputation: 0

Unread postAuthor: daberno123 » Mon Jan 11, 2010 8:15 pm

As far as rifled barrels go, Crosman sells replacement barrels that are 24" long in .177 and .22 and they are both under $20 I believe. Anyone who has modded a Crosman gun probably knows this but I don't think I've ever seen anyone use one of their barrels in a conventional "spudgun" design.
  • 0

User avatar
daberno123
Colonel
Colonel
 
Posts: 594
Joined: Mon Nov 19, 2007 5:56 pm
Location: Ohio
Reputation: 0

Unread postAuthor: Gippeto » Mon Jan 11, 2010 8:16 pm

Personally, I'm leaning toward a modification of the Brocock cartridge as a valve. Basically, they are a partially balanced spool valve. (But then...so is every piston valve ever built....think about it. :wink: )

http://www.google.com/patents?id=_Pk0AA ... q=&f=false

Pneumatic actuation could be accomplished via hammer valve, or simply use the hammer directly by retaining the directional differential of the brocock cartridge.

Forget barrel making though...by the time you get just the hole drilled, you'll have invested enough to purchase several Lothar Walther barrels. Crosman barrels are MUCH cheaper yet.

Track of the wolf is another source for...larger caliber barrels. Up to .750" in smooth bore... IIRC.

As far as breech design goes, I've been tossing around two alternatives. The Air Force "sliding breech cover", and a swinging breech, which also allows loading directly into the barrel, but would allow for a "tapered" section between the valve and the barrel ( or minimized dead space). I've only seen this breech type used on one type of philippine built air rifle...cannot remember which one.

I rather like the idea of the Air Force tube frame, which is used to mount the barrel in bushings...it would allow quick "allen wrench" caliber changes. 8)

Enough of my idle ramblings...anyone else have a thought to share?? :)
  • 0

"It could be that the purpose of your life is to serve as a warning to others" – unknown

Liberalism is a mental disorder, reality is it's cure.
User avatar
Gippeto
Donating Member
Donating Member
 
Posts: 2393
Joined: Sat Jan 19, 2008 10:14 am
Location: The Great White North...Canada eh!
Reputation: 11

Unread postAuthor: twizi » Mon Jan 11, 2010 8:22 pm

also found this thought it may help

http://www.ora8i.rivington-riflemen.org/PCP%20Factors.html



this design would be perfect for a chamber sealing pistion valve idea
the pic that polandspud posted it could be acuwated with a ball valve or blow gun or we could use btb 40 bar balanced push button valve we could up the presure say to 1500psi

i say we should have a 50 cal bore or bigger [/img]
  • 0

Last edited by twizi on Mon Jan 11, 2010 8:52 pm, edited 1 time in total.
dont play with airsofter with 1000$ gun and play with a 5 dollar pair of glasses
User avatar
twizi
Colonel
Colonel
 
Posts: 511
Joined: Thu Nov 27, 2008 9:04 pm
Location: up yours
Reputation: 0

Next

Return to Non-Spudgun Related Discussion

Who is online

Registered users: Bing [Bot], Google [Bot], Google Adsense [Bot], Yahoo [Bot]

Reputation System ©'