Help me see if I missed any big flaws please.

[sssssbooom]

Hey guys it has been a while scene I have made a gun so I started to make one.

I have made all the cuts. All I have left is to make a piston, barrel support, and then solder it all together.
I have never made a coaxle or a piston gun before, but I did a lot of research (thanks to wiki and some stickys.) and I think I am doing every thing right. But a second (or 3rd, 4th, etc.) look will determine that.

The upper camber is 3/4" and 26" long
The inner (coaxle) barrel is 1/2" and I haven't decided how long I want it yet.
The lower camber is 1" and 21" long
Any Thing I missed that would help please ask

Full view


The back end


And here is my absolute worst area of experience. (I got none)
This is my Idea for a piston


One more question, would wood be okay for use with a piston? I am a hobbyist wood turner and I could turn one on my lathe real quick with a set of callipers.

Thanks a ton guys,

BOOOM

P.s. sorry for the picture quality all I have is my phone.

[Crna Legija]

i cant see enything wrong with that design
wood is good for for a piston as long as you seal the wood with vanish so it doesn't absorb water and expand

[spudtyrrant]

Your pilot valve is too small,and pilot volume too big(waiting for jack....) i would get a ball valve or qev. Besides that it looks good, especially for your first .

[mark.f]

So it's a coaxial with an "extended" larger air chamber? That's pretty cool... not something I've seen a whole lot.

Thanks for lurking. As spudtyrrant said, your pilot volume could use a little downsizing, though.

[Gun Freak]

Thanks for lurking. As spudtyrrant said, your pilot volume could use a little downsizing, though.

He might not know what pilot volume is...

Yeah you definately need to upgrade your valve... It might not even acuate with that valve. QEV probably would be best... if you want to spend the money. Also you may want to put a quick disconnect on instead of the schrader... that is a schrader right? I cant tell. The piston in my coaxial doesn't move when I fill it through a schrader, but its big. You will preobably be fine. Looks good though

[sssssbooom]

Good, so all the stuff on the back end may need a little fixing, but other than that I am good right?

So it's a coaxial with an "extended" larger air chamber? That's pretty cool... not something I've seen a whole lot.

Yeah later on I plan making a wooden stock with the bottom sticking out. So it looks kind of like a grenade launcher.

[Brian the brain]

You should be able to trun nylon on a wood lathe.
That would be better piston material..

If you could place the valve right at the tee that connects the lower chamber you will get better flow.

Now I don't see any benefit from it that a longer coaxial chamber could not provide.

[sssssbooom]

Here are pics of my barrel support and piston

I actually turned this flush bushing reducer on my wood lathe to fit inside 3/4 type M pipe then filed some air holes. I think it turned out great but the copper dulled the crap out of my tools.


I used wood because I have it on hand. If I had some acrylic on hand I wound have used that. And if anyone is interested the type of wood is purple heart. I use it because it is very dense. if it doesn't turn out I will get some nylon.


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