Haven't gone unregged yet but the first time I fired it with a 1"ballbearing @600psi it kicked so hard it broke off the brass fitting that the blowgun was attached to, and put me on my butt... After that I put on a 3/4" street 90 with the ballvalve and filler adapter and use the ball valve as a trigger(this friday I'll be getting a check/filler nipple and will run it off the back of a tee that'll replace the str90 and use the 1/4" ball valve as a trigger only<the>)....
I'll post some damage pics later.....
I used Iron for the chamber because I didn't have the money for brass/copper fitting for copper chambers yet....
Specs are: 1.5" porting , toolie styled barrel sealer, 1" type k barrel, 3/4" qev as the pilot valve...
I've also got to build a mount/tripod for this thing, it weighs about 30lb and will bruise your leg if you brace it against your thigh...
I also forgot to mention how much of a pain it is to make a piston that'll handle 600psi+ without self dectructing the sealing face every shot...
And yes, thats my gawdawfull ugly brazing job on the piston chamber, and LIBERAL use of pipedope on the threaded portions....
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Posted: Tue Jul 07, 2009 1:53 pm
by jackssmirkingrevenge
Looks awful but pretty is as pretty does, looking forward to the damage pics
Also, if you run out of air, looks like you can swing it from the barrel as a war-hammer
Posted: Tue Jul 07, 2009 1:56 pm
by jeepkahn
jackssmirkingrevenge wrote:Looks awful but pretty is as pretty does, looking forward to the damage pics
Also, if you run out of air, looks like you can swing it from the barrel as a war-hammer
But with a 50lb co2 tank, air is plentiful..
As you can tell by the pics, the wood is not rotten and that's a ' steel ball for size index...
Posted: Tue Jul 07, 2009 2:31 pm
by neeewwww
Beautiful war-hammer... Notice you can use your warhammer as AirGun.
I like the... ... "old" look.
Piston pics?
o>
-- Edit
*I found the piston...
Posted: Tue Jul 07, 2009 3:05 pm
by jeepkahn
I was going for the same look as the AMS Avalaunchers, hence the sidebyside chamber layout, when I get the copper chambers built the weight an bulky look will hopefully go away... but I don't know if you want hold something lighter while firing when the recoil is so ferocious...
I'm sure one or 2 on here have fired a highpressure large bore gun, but those who haven't....It's a definite wakeup call....
Posted: Tue Jul 07, 2009 3:20 pm
by spudtyrrant
jeepkahn wrote:But with a 50lb co2 tank, air is plentiful..
with a 50lb co2 tank co2 is plentiful
Posted: Tue Jul 07, 2009 3:23 pm
by jeepkahn
spudtyrrant wrote:
jeepkahn wrote:But with a 50lb co2 tank, air is plentiful..
with a 50lb co2 tank co2 is plentiful
I stand corrected...lol... Smart@$$....
Posted: Tue Jul 07, 2009 6:10 pm
by mark.f
Looks... um... good.
Need more details on piston, sealing face, etc. Good job!
Posted: Tue Jul 07, 2009 6:17 pm
by Clarke
Cant wait to see some damage vids. High pressure damage is always impressive especially at 600 PSI
Posted: Tue Jul 07, 2009 6:29 pm
by THUNDERLORD
Sweet!! "war hammer".
I was thinking it could have two "45's" off the "Cross" between the chambers and valve.
That way it could be strapped on the shooter's wrist, like a bull-pup pistol maybe. 8)
Posted: Wed Jul 08, 2009 5:58 am
by jackssmirkingrevenge
Very impressive penetration, any idea at what rate it screams through the air?
Posted: Wed Jul 08, 2009 8:54 am
by jeepkahn
Some better pics of overall size and layout, as well as the fire control that will be upgraded soon... Also a pic of the c02 adapter setup I use to fill with....
I've tried to get readings 3 times, but at 6ft away firing 16" above the chronie, the muzzle blast kept knocking the chrony off the stand, I'm going to mount it to a steel plate 12"x12"x.125"thick and clamp that to the picnic table...
The piston is 3/8" threaded rod, 2 3/8"x1.5" washers spaced 2" apart with a rubber "flapper" seal that allows air to enter chamber but 100%seal on firing, the sealing face is .25" flange gasket rubber(we have a local company that makes large high pressure flange gaskets And I get the scraps for free, durable hi durometer stuff), with a fender washer behind and a smaller washer in front( the problem I was having in the begining was too small a washer on the barrel side and when I'd fire it the sealing face would get launched as well).... this piston has more than required travel (about 5/8") but I only did that so that the nut and rod can pull back even with the breech....
Posted: Wed Jul 08, 2009 10:55 am
by THUNDERLORD
Looks even more awesome in the close-up pics.
That barrel grip looks a little...scary to hold right there.
Is the barrel sleeved?
...@600psi it kicked so hard it broke off the brass fitting that the blowgun was attached to, and put me on my butt... After that I put on a 3/4" street 90..
Recoil
So you're sure the recoil broke the brass and it wasn't failure???
BTW:Brass fittings are confusing to me, the other day my (cast brass) garden hose faucet body was spraying water streams through tiny holes in it.
Must've been due to freezing water...Which of course got me to wondering what pressure water-ice could potentially generate and thoughts of a "green" design where water freezes at night, compressing air for motors...It would only work in certain climates and the set-up would probably require ingenouity due to the slow freezing rate of large bodies of water. 8)
Posted: Wed Jul 08, 2009 11:50 am
by jeepkahn
THUNDERLORD wrote:Looks even more awesome in the close-up pics.
That barrel grip looks a little...scary to hold right there.
Is the barrel sleeved?
...@600psi it kicked so hard it broke off the brass fitting that the blowgun was attached to, and put me on my butt... After that I put on a 3/4" street 90..
Recoil
So you're sure the recoil broke the brass and it wasn't failure???
actually the nipple connecting the tee to the qev sheared, so yes, I would say that the recoil did it, especially since this thing has a teensy bit of recoil....
the grip on the barrel is just for carrying it, that's where it balances at...I'll be building a bipod for it this week...
Posted: Thu Jul 16, 2009 8:44 am
by jeepkahn
Here's the updated triggering mechanism I built to replace the blowgun triggered broken one.....
Also pics of the decimater "field stripped", the piston(showing the toolie design), and the piston/pilot chamber( gives a good visual of how I build the "cup seal" rear piston seal that is so effective for allowing only one way flow for filling and 100% seal against backflow on firing)...
The reason for the big rubber stopper behind the barrel sealing face is because with unregged co2 and a washer directly behind the sealing face, a coupla shots would destroy the sealing face by turning the barrel into a hole punch, the rubber stopper helps cushion against that....
Do you think a 3/4" qev is overkill for a 2 cubic inch pilot volume???
