For 35 bux just buy a cheapo gun and modify it Like So. I wish more people used this idea. It is amazingly cheap, simple, effective, and realistic.

No gravity in your area then

You sure it's just my area? I thought everyone ate breakfast on the ceiling...

Hey guys. First of all Caz, the chamber is actually under the barrel. Its the shorter tube. The stock is not part of the chamber, and does not need to be.

I run it around 110-120 psi only because I dont not have access to any high pressure source. I have been thinking about making a smaller bore ...

So it has been a while... A long, and somewhat painful while without being able to build. But its summer again here and I am at home again with full access to weapons building tools and a larger bank account due to an actual job. After a day with an old friend who wanted to plink a little, I ...

I was simply commenting on the performance of a ball valve/spring combo, and attempting to see if anyone else had had such good luck with this setup.

Velocity made a large bore semi-auto, tank killing, destroyer sinking, world ending weapon of mass destruction that the US needs to copy and use ...

Alright. I might give ebay a shot. I have had poor luck finding stuff there recently. Does anyone else have first hand experience with this situation? Is there anything else I should think about?

EDIT****

So I decided I might try SCBA tanks, either through ebay or I might try at my local fire ...

I happen to have seen a lot of threads about compressors lately... maybe that's just me...

Anyway, I was wondering how many people built/bought resevoir tanks for their fridge compressor, and what they built them out of. I might have the option of getting ahold of a compressor from a large freezer ...

As much as I love this idea, I think you could have gone a simpler, and more realistic route. Jonny Boy had a really good idea here. If you were planning on cutting up an airsoft gun (what specific gun is it btw?), you might've wanted to do something like this instead.

Other than that little point ...

So Jack, why exactly do you have doll sized guns laying around your house?

Great job on the servos though. Cant wait for the finished product.

well... I am almost at a loss of words after seeing how crazy big that is...

The pool noodle idea should still hold true though. Just cut it into 4 parts, and maybe take off a little extra material off where the fletches are. Should work just fine. Plus you can find them at target, dollar stores ...

yup. that would be it. the chamber still seals completely, but you dont have to muzzle feed the darn things. Oh, and it works pretty well with round ammo because they roll down the barrel.

The "breech loading" coaxils aren't full breech loaders. The breech is attached OUTSIDE of the chamber in a setup like this, where it is in a bull-pup configuration, the velocity isnt harmed as much because you can attach a long barrel and make up for the dead space.

The cannon is in the hybrid showcase (UPGBH10x)

Actually I was refering to your ammunition. What are you using as "penetrator" rounds?

Hmm.. could you link to your round. It has been a while since ive seen this thing...

Perhaps this may be of service. This was designed for use with 2 inch vortexes, but being foam, it could work.

600 psi is nothing to one of these. I believe either Brian or Poland (or both) once took theirs over the 900 psi mark. These things are designed to do a lot of work.