Short question topic

[Air2theBrain]

May i ask a favor, i've been on my laptop for a few hours doing a lot of reading of members posts, but Jack and Farcticox1 may i ask for some links to your semi-auto cannon builds?

Also small ones if you have them, i'm wanting to make a small pistol plinker also and would love some ideas?

[farcticox1]

this is mine http://www.spudfiles.com/airsoft-pellet ... 26679.html shows how the semi auto bit works, quite bulky though so I don't think you could shrink it down much.

[hectmarr]

I would not recommend it, epoxy resin is a far better choice for pressure-bearing components.

Ok. I take the advice as a guide. The question had its origin in that I have enough of this resin, although it will not work, I imagined it, although I was not sure. It is not worth the risk of trying to risk damage to me. Thank you

[Air2theBrain]

this is mine http://www.spudfiles.com/airsoft-pellet ... 26679.html shows how the semi auto bit works, quite bulky though so I don't think you could shrink it down much.

Many thanks!

[jackssmirkingrevenge]

This is my better known prototype:



[youtube][/youtube]

This one was full auto without a blow forward bolt, simply using an "airtight" magazine:



[youtube][/youtube]

This works best for spherical projectiles:



My most sophisticated design to date used ejecting cartridges:



[youtube][/youtube]

[Air2theBrain]

LOVE the shell ejecting cartridges!

Thanks Jack much appreciated.

I'm going for a top rail ammo feed, will eventually do a bottom mag feeding upwards. I was playing around with one i made up quickly a couple of months ago and it seemed to work well but i wasn't firing them just manually feeding/pushing them along until i used a make shift spring to feed them which had a plate attached.

Just finding a spring long enough to go almost the length of the barrel is going to be fun...

[hectmarr]

Very inspiring the video of the cartridges being ejected, I like it!

[Air2theBrain]

HI guys tomorrow i will be ready to pressure test my first main chamber.

Just wanted to ask, is filling the tank with water and applying pressure the best way to test it?

[jackssmirkingrevenge]

Just wanted to ask, is filling the tank with water and applying pressure the best way to test it?

A hydro test is definitely preferable in terms of safety in the event of failure, but also make sure that you can dry it out completely afterwards to avoid future corrosion from trapped condensation.

[hectmarr]

Oil of little price can be used, although I am not very sure.

[jackssmirkingrevenge]

You have to be sure that it doesn't attack synthetic materials like o-rings though.

[Air2theBrain]

Thanks very much for the replies Jack & Hectmarr.

The chamber will be capped off, not attached to the qev or anything and can blow it out with compressed air.

Will only be taking it to 160-180psi today and hopefully its air tight.

[Air2theBrain]

Whilst waiting for my tanks to be ready for testing, i thought i'd start piecing together my small copper canon pistol.

Did a bit of reading last night about hammer valves...knew i had an old air gun sitting in the garage, so i stripped that and was left with a very strong hammer valve.

I'm trying to work out a trigger mechanism for it but for the life of me i can't figure it out even after all the pics i've seen.
There were some threads where the photos weren't available..but yeah a little stuck at the moment with how to build a trigger mech!

I know the valve needs to be chopped down for its too long, the spring is nice and strong so i see it having no trouble doing whats it supposed to do.

I know i can use something that will do exactly whats needed, but i want this one to be all hand built if i can.

Appreciate any help thank you.

Heres what i've mocked up currently.

[jackssmirkingrevenge]

Pressure usually plays a role in sealing "pistol" type blowguns, so connecting what is usually the output as an input could result in a leak.

I'm trying to work out a trigger mechanism for it but for the life of me i can't figure it out even after all the pics i've seen. There were some threads where the photos weren't available..but yeah a little stuck at the moment with how to build a trigger mech!

Here's a nice interactive animation showing how a pump-up pneumatic rifle with a hammer valve works.

http://www.arld1.com/images/swfs/mechan ... umatic.swf

[Air2theBrain]

Thats awesome thanks Jack, reading it now.

Oh the valve pictured, is that good to use for a hammer valve?