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Update:6mm spare parts gun

Posted: Fri Mar 21, 2008 10:33 pm
by bigbob12345
Well this is my first coax that has lasted for more than one day(made one out of copper and my crappy soldering broke :evil: )
so threw this together last week completely out of spare parts.
and im going to call it my first coax because my actual first blew out as described earlier.

It is very basic nothing new except for the exchangable barrels which is also very basic and i will explain later.

specs
chamber:8in of 3/4in pvc pipe
barrel:8in of 6mm aluminum pipe, and 15in of .177(metal bb size)
Valve:coaxial piston valve
exhaust:heavily modded blowgun(I spent more time modding the blowgun than working on the rest of the gun)
Fill method:scrader valve
and i attached the barrel to the gun by epoxying it to a 1/4in nipple(6mm fits inside it well)and then threding tht into reducers.
The same method is used for the .177in barrel except I reinforced the epoxy with wire mesh because i dont want it to blow out like my last coax did.
I also realize it is messy with the primer so dont comment on that
Pics

the gun
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A blurry pick of the barrel epoxyed to th 1/4in nipple
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how i am capable of exchangeable barrels
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The piston(a 1/2in copper cap with neophrene epoxied to the top and duct tape wrapped around it for a better fit)
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My horrible priming job(will paint in a day or two)
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Thats it

Edit: Ive got some damage

All shots are at 160psi which is my maximum operating pressure

first is a nail that happened to fit perfectly in the barrel vs a candle

before
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after
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next at elitesnipers request, a 0.2 gram airsoft BB at a shook up soda can

Before the shot
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after the shot(notice the small hole in the other side :wink: )
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Next shot was a 0.25 gram bb vs a film canster, it made it through both sides in one shot which i was impressed by

the entry in the cap(looks kinda small in this pic)
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the exit in the other side of the canister
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And I upgraded the pilot to a 1/4in ball valve i had lying around. It raised power a lot
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and i just GGDT'ed it and got 760fps with a .12 gram bb at 160psi which i was very surprised by.

Posted: Fri Mar 21, 2008 10:39 pm
by elitesniper
haha, nice little plinker :wink:

Posted: Fri Mar 21, 2008 10:40 pm
by bigbob12345
Thanks
Ill shoot some "damage" shots soon and post em :)

Posted: Fri Mar 21, 2008 10:46 pm
by elitesniper
haha, liked how you said ''damage'', since it's really small doesn't mean its not capable of destrustion :)

Posted: Fri Mar 21, 2008 10:50 pm
by bigbob12345
but it is capable of penatration :wink:

Posted: Fri Mar 21, 2008 10:52 pm
by elitesniper
yep, ohh shoot shaken up coke cans :D oh and where did you get your 6mm pipe? does it fit bb's loosely or JUST right?

Posted: Fri Mar 21, 2008 11:00 pm
by bigbob12345
i got the 6mm pipe from a broken crappy $10 airsoft gun that broke within minutes of the first shot.
so it fits them perfectly

Posted: Fri Mar 21, 2008 11:01 pm
by Counterstriker
I thought copper was a horrible material for pistons? And btw lok what I got for pistons..http://www.eti-usa.com/images/CastinCra ... -32-oz.jpg

CASTING EPOXY at a craft store..

Posted: Fri Mar 21, 2008 11:04 pm
by bigbob12345
Well i was out of the glorious stuff(you know of what i speak)and i had this endcap
It has performed great so far and it has a bumper so i cant see anything happening to it.
And to fix the link put a space between the url and the periods.

Posted: Fri Mar 21, 2008 11:30 pm
by Counterstriker
bigbob12345 wrote:Well i was out of the glorious stuff(you know of what i speak)and i had this endcap
It has performed great so far and it has a bumper so i cant see anything happening to it.
And to fix the link put a space between the url and the periods.
:wink:

Posted: Fri Mar 21, 2008 11:32 pm
by bigbob12345
hahaha thats great :lol:

Posted: Fri Mar 21, 2008 11:48 pm
by elitesniper
haha wait till jsr sees that :wink:

Posted: Sat Mar 22, 2008 9:48 am
by Counterstriker
Yah :D Well I like the gun, Where did you get the shrader? I can't find the one with 1/4 threads on one end.

Posted: Sat Mar 22, 2008 10:00 am
by bigbob12345
I got the scrader at ace hardware for the cheap price of $2(of course it was not bought for this gun).

Posted: Sat Mar 22, 2008 5:14 pm
by bigbob12345
Well i have updated the original post with some damage pics
and i upgraded the pilot from a blowgun to a 1/4in ball valve and it is much more powerful now
GGDT says this gun fires a .12 gram bb at 760fps at 160psi.
I was surprised by that too