SpudFiles

hey that's nice... can't wait to see it
where do you get all those springs from ?

POLAND_SPUD wrote:hey that's nice... can't wait to see it

The plan is to hook it up to my shock pump tomorrow afternoon to see at what pressure the BB will "pop", then try it out with the chamber.

where do you get all those springs from?

Well... everywhere I like to cannibalise items before they are thrown away and I keep all springs, irrelevant of whether I think I'll use them or not.

I'm sure you can buy boxes of assorted springs though.

Wow!! great work, cant wait to see if this works? if so I'll start construction on one a little different................

Unfortunately the power was out at home yesterday so I wasn't able to do much testing but I hope to have some results by this afternoon. There might be some issues with sealing at the breech because I probably used the wrong sort of tubing but I will remake it if that is the case, if we can come up with a simple barrel/magazine design that will work well with a CO₂ inflator it will make portable pistols available "to the people" for all those who don't have the benefit of easily obtainable commercial airguns, so worth the effort

edit: As I suspected, the BBs aren't sealing properly in the breech so not enough pressure can be generated to fire them. Time to start over, but probably tomorrow, I want to play with my camera

Any luck getting this to work Jack??,I seen a kid on you tube using a co2 inflator with a small tube and firing BB's( plastic) at a tin lid but it looked very lacking power wise!.If these inflators will only fire BB's= ( I intend on steel .177) with piss weak power I won't waste my time,I was sure these inflators somehow regged the pressure down to 100 psi which would explain the weak power?............

EDIT here's the You Tube clip

[youtube][/youtube]

django wrote:Any luck getting this to work Jack?

Unfortunately ever since I got the camera I've done no construction work whatsoever I'll try and do something this weekend though.

I was sure these inflators somehow regged the pressure down to 100 psi which would explain the weak power?

I think it's not a matter of pressure but flow, the gas comes through a port that's around 1mm (or less, I don't have it in front of me but it's tiny) in diameter, it's practically leaking through into the chamber, which is why some sort of detent is needed to hold back the projectile while enough pressure builds up behind it for decent power.

See Ive never looked at one of these inflators well enough and had no idea the port in the nozzel was like 1mm!! sounds like I need to find another way mate?,unless these inflators can be modded?......

django wrote:unless these inflators can be modded?......

You could always drill it out but then you're still limited by the flow from the valve, so I would still incorporate an airtight detent, it will improve power as well as limiting rate of fire.

Edit: Also, the guys in the video you posted are firing through a schrader, so flow is even more limited!

I'm thinking of making a simpler version that removes the need for a tee magazine and spring:

I used a similar " fake" bulb to avoid spending all those 12 grams during testing on my Pnuzi..

You could switch things around and have the mag running under the barrel, then an elbow before ammo enters the barrel.
This would require airflow from below though.


I think I'm gonna go for a revolver next time built around my push button valve, an elbow and a 12 gram adapter..

You all know I'm a bit of a compactness freak..always thinking about ergonimics besides performance. I'm confident your T design can be re-arranged so it fits inside a pistol shape while still performing at it's full potential.

You might want to consider a fake silencer to hide some extra barrel length...

Brian: the mag set up you describe is exactly what had in mind anyways
Jack:with that latest diagram you would have to take the barrel off every reload ,unless Im missing something?.

I have an old Broken 1911 Airsoft springer but im pretty sure I can't get a co2 bulb etc in there!. Also have an old steel 357 Blank gun revolver thats broken,might be able to modify that one with a hammer valve of some sort but will have to be small!. This is the problem guys, trying to scale down internals to fit into a pistol frame, I REALLY want to make this co2 pistol

Brian the brain wrote:You might want to consider a fake silencer to hide some extra barrel length...

Are you throwing my suggestions back at me

You could switch things around and have the mag running under the barrel, then an elbow before ammo enters the barrel.
This would require airflow from below though.

I tried something along those lines here but it didn't really work out. The concept is probably sound but my construction wasn't

with that latest diagram you would have to take the barrel off every reload

Or you could reload through the muzzle

Now that the camera battery is charging I found time to make a prototype, I included a diagram of the actual construction below. I tried to make it as simple as possible, let's hope it works

wait sorry I missed this and I'm pretty late, but this guy wanted to build a bb pistol, he wasn't sure how to do it but why didn't any one refer to the works of antonio?
come on, ant was the man, he had the goal to create practical easy to replicate designs for portable pneumatic hammer valve bb guns, and he did a pretty dam good job,

if your familiar with the engineering process crap, they say your supposed to identify the need, the actual need of the client, you claim you need a CO2 bb pistol, I think you looking for a single action repeater or a semi auto hand held bb gun, so I think it's relevant to look into using liquid propane (which is what airsoft green gas guns use because it re-vaporizes at a manageable lower pressure making a semi self regulating low pressure high density air supply) and a soda bottle air supplies commonly used in ant's designs I understand if you would automatically want to eliminate this option though

so check out some of the ant designs here:
http://www.spudfiles.com/forums/p-3-sta ... 12220.html
http://www.spudfiles.com/forums/p-4-bb- ... 12216.html
http://www.spudfiles.com/forums/p-2-ver ... 12712.html
http://www.spudfiles.com/forums/automat ... 13665.html
i don't mean to bash anyone so I apologize if I sound like I am

I'm sure you can buy boxes of assorted springs though.

Yes, I can confirm this. I actually sent away to a catalog for a set of assorted springs and a set of assorted sizes or brass, copper and aluminium pipes. You can get all sorts of sets of compression and tension springs from different scale model and small parts manufacturers.