20mm Airgun MkII

[HunterT]

When building my first airgun/cannon I used DWV piping without knowing that it shouldn't be used for airguns. So I took apart that airgun and built this one. I've reused the breech, barrel, and sprinkler valve from my first version. It now has a bigger, pressure rated PVC chamber. I built it to resemble the Lahti L-39 anti tank rifle, however mine will not be taking on Russian tanks. I still want to add a magazine on the top and a few other things.

I've used it up to 60 psi at the max and I usually use it at ~40psi. I've shot it at empty milk jugs filled with water and the water goes flying.

[JDP12]

looks good, but i would advise not using PVC in cold conditions, since it can become bitter and fragment explosively, which could lead to serious injury

[jackssmirkingrevenge]

i would advise not using PVC in cold conditions, since it can become bitter

Indeed, PVC is notoriously spiteful at lower temperatures

(itouch I assume )

As to the subject of this thread, it would benefit from modding the sprinkler valve, especially as you have a relatively small chamber running at relatively low pressure, but not bad for a second effort

[JDP12]

yea good old itouch.... and some retardedness on my part.

[HunterT]

...i would advise not using PVC in cold conditions, since it can become bitter and fragment explosively, which could lead to serious injury

Is this a danger if I'm only outside with it for five minutes? The rest of the time I store it inside my house.

...it would benefit from modding the sprinkler valve...

I tried to order a blowgun trigger from amazon.com, but they don't deliver compressed air equipment to Alaska. I have the tubing and such. Tomorrow I'm going to look for one at our local auto parts store.

-HunterT

[JDP12]

yea then its okay probably. You don't want the temperature of the PVC to drop significantly, which would happen if you leave it outside for extended periods. Stepping out of your house to shoot is a little safer.

[HunterT]

Stepping out of your house to shoot is a little safer.

That was my logic. Thanks.