copper looks cool...

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mobile chernobyl
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Tue Dec 26, 2006 12:12 am

Well i got bored waiting for the parts for my 3" porting 3000 cu in mega cannon, so i decided to build a copper sniper rifle. my first venture into copper mind you...

[albumimg]276[/albumimg]

Chamber: appx 3+ feet of 1.25 inch copper pipe (i say 3+ cause of all the FRIGGEN EXPENSIVE copper fittings.)

Valve: combination metal/nylon/silicon piston with dual seals, very lightweight and works flawlessly (on the first try too!)

Valve Exhaust: 1/2" ball valve (also aids in filling, that design is soon to be changed tho) positioned with 1/2" black iron and fittings to be right near handle. very ergonomic and helps maintain the "sniper rifle" feel. to fire, thumb pushs ball valve lever forward fastly and user hears a pleasing loud "pshh" as projectile flys out barrel.

Barrel: 5ish feet of 1/2" copper pipe. soon to be replaced with alluminum or steel with a union to connect to existing copper (needs to be replaced because just the force of the hose clamps dented it and now AA batteries sometimes get stuck in it where they are)

I think it turned out pretty good. I don't usually do plumbing, so sweating the copper was kind of a hit or miss practice at first - But i can gas weld and braze pretty damn good. So i just made sure that there was plenty of lead in every joint then i tried to fillet it around the edges to make it look good/give me more peice of mind if im ever to venture above 110psi.

[albumimg]277[/albumimg]

First impressions...

HOLY SH!T haha. well actually it took me a while to figure out that the valve was not venting fast enough so the performance at first was like, wheres the beef??
I have to fill with the male fitting on then take it off to fire so that it vents fast enough. I think this will be solved when i put a bigger oring on the piston to help seal it.
My estimation is that its easily doing 500-600 fps with just 110psi, a marble and 5' of 1/2" copper. Heres some damage pics of it firing other stuff including a AA Battery (my personal favority projectile!)

FRONTAL VIEW
[albumimg]279[/albumimg]

REAR/CARNAGE VIEW
[albumimg]280[/albumimg]

Mind you, that is through 3/4" (more like 7/8" light) Solid pine. yea yea yea, pine is soft wood. Well not pictured, but the regular nail with tape sabbot easily penetrated 6/4" hard maple with only 80psi. Pretty gnarly d00d.

So until my parts arrive for what just may be the biggest/coolest portable mega launcher spudfiles has ever seen (short of a pumpkin chunkin competition cannon) I plan on making 1 more copper air rifle. Why make 1 with interchangable barrels when there just that fun! I have like 5 feet of 2" copper and a good amount of 1" copper, here is my goal.

Make a gun to launch 12gr CO2 powerlets with tails (800psi filled powerlet flying at 600 fps into a hard solid test target = kablam? teeheehee)
- anyone know what size copper/PVC i would need to make a good bore match for a 12gr CO2 powerlet?
Last edited by mobile chernobyl on Tue Dec 26, 2006 12:21 am, edited 1 time in total.
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experament_u2
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Tue Dec 26, 2006 12:18 am

trippy design but a good gun nice work
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Tue Dec 26, 2006 12:24 am

Wow... that thing is odd looking but so cool. Nice job. It's like abstract art meets homemade weaponry!
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mobile chernobyl
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Tue Dec 26, 2006 12:38 am

Yea i guess it is kinda "odd looking" lol but i kept it "abstract" or simple so that there would be as few bends as possible to improve airflow.

Its designed to be held like a modern armyish/bullpup rifle, with a buttstock (the 90* bend portion in the rear), a handle (kinda obvious, but the piece inbetween the two tee's), and a place to put your front hand on for stabilization when taking aim (the section of pipe inbetween the two 45* fittings).
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Bluetooth
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Tue Dec 26, 2006 10:06 am

Thats awesome. I've always kinda liked those sniper rifle designs but everyone makes the design thats on PVC Ballistics :( .
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mobile chernobyl
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Fri Dec 29, 2006 1:16 am

Bluetooth - Yea i definately agree that the pvc ballistics design is worn out and it got poor flow with all the bends and it all leads up to a weak 1" sprinkler valve. I'm sure it still packs a punch, but i think my design looks a little cooler, or abstract is it? lol.


well heres the pics of both guns
[albumimg]281[/albumimg]

a little closer
[albumimg]282[/albumimg]

closer yet, with a better view of the valves and fill/exhaust pipe routing
[albumimg]283[/albumimg]
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