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Detent BB Gun V2

Posted: Sun Jan 16, 2011 4:30 pm
by Gun Freak
OK this is the third time I had to type this so I'm really pissed off :lol:
So not much really, just a tentative design to test the concept before I go all out on a skirmish-able airsoft gun. It's POLAND_SPUD's detent design with brass fittings and a connection for my fire extinguisher air tank. Once it's all done I'll post it in the showcase. At a pop pressure of 100-120 psi, it can go 650 fps, and I haven't tested higher. I usually put a little more than 120 in the tank to get it to pop. So here are a few pictures of the gun and dammage.
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The layout is a bit different than in the pictures but it's the same idea.
It can shoot through 4 cans at once. In the video though it is only 3 :?
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Videos
[youtube][/youtube]
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The galvanized might be replaced with brass to make it look cooler 8)
I think it deserves hop-up, any good ways to implement it?

Posted: Sun Jan 16, 2011 6:03 pm
by POLAND_SPUD
What about feeding? how reliable is it ?

Posted: Sun Jan 16, 2011 6:13 pm
by Gun Freak
POLAND_SPUD wrote:What about feeding? how reliable is it ?
Well I can't really say because my chamber isn't really big enough for enough bb's and my air source isn't constant. Tomorrow I can get my compressor hooked up and see. So far it has been pretty good. I was trying to think of a way to make it semi but so far I haven't thought of anything. I was thinking sort of like your pneumatic cylinder setup, but I think full auto would be better anyway.

Posted: Sun Jan 16, 2011 7:59 pm
by jackssmirkingrevenge
Gun Freak wrote:I was trying to think of a way to make it semi
Have you tried careful trigger control? Looking forward to seeing it in action, good job!

Posted: Sun Jan 16, 2011 8:48 pm
by Gun Freak
Thanks, I'm editing the vids into the first post now. Better vids are to come.

Posted: Mon Jan 17, 2011 11:55 am
by saefroch
You might want to anchor the target(s) next time :wink:

Posted: Mon Jan 17, 2011 12:04 pm
by Gun Freak
saefroch wrote:You might want to anchor the target(s) next time :wink:
That's not a bad idea :P I didn't even think of that... :lol:

Posted: Mon Jan 17, 2011 12:45 pm
by POLAND_SPUD
lol it sounds exactly like mine

if you reduce the flow of air from the air source to the gun you might be able to bring ROF down... anything that reduces flow should be ok

ohh BTW have you got a compressor ? I understand that you want to keep it portable but since you're still developing it then you might want to hook it up directly to the compressor... well at least for me that seems more convenient

Posted: Mon Jan 17, 2011 8:27 pm
by Lockednloaded
What's the ID of your washer? And can you raise the popping pressure by tightening the fitting?

Also, what's the ID of your barrel?

Posted: Mon Jan 17, 2011 8:37 pm
by ramses
good god. skirmishing at 650 FPS? You could use a regulator to bring the tank down to a reasonable pressure while storing more air.

Posted: Mon Jan 17, 2011 10:15 pm
by Gippeto
ramses wrote:good god. skirmishing at 650 FPS?
Exactly what I was thinking.


:roll:

Posted: Mon Jan 17, 2011 11:33 pm
by Hotwired
Gippeto wrote:
ramses wrote:good god. skirmishing at 650 FPS?
Exactly what I was thinking.


:roll:
Gun Freak wrote: a tentative design to test the concept before I go all out on a skirmish-able airsoft gun

Posted: Tue Jan 18, 2011 5:15 pm
by ramses
Gun Freak wrote: a tentative design to test the concept before I go all out on a skirmish-able airsoft gun
[/quote]

typically, the all-out version is designed for moar power, ROF, efficiency, etc.
But I see your point.

Posted: Tue Jan 18, 2011 7:10 pm
by Gun Freak
POLAND_SPUD wrote:if you reduce the flow of air from the air source to the gun you might be able to bring ROF down... anything that reduces flow should be ok
I think I'll end up using a blowgun for the main valve, so the flow should be restricted quite a bit.
ohh BTW have you got a compressor ? I understand that you want to keep it portable but since you're still developing it then you might want to hook it up directly to the compressor... well at least for me that seems more convenient
Yeah I just didn't have an 1/8" port on the gun to use off a blowgun but I'll figure something out for using the compressor.
What's the ID of your washer? And can you raise the popping pressure by tightening the fitting?
It's a 1/4" ID washer, and yes, tightening the bushing squeezes the rubber washer and makes the whole smaller. But after repeated use, the hole gets smaller, but I can take it out to make it bigger again.
Also, what's the ID of your barrel?
6.35mm
good god. skirmishing at 650 FPS? You could use a regulator to bring the tank down to a reasonable pressure while storing more air.
Regulating won't be nessecary-- controling the flow out the main valve along with adjusting the pop pressure is fine for controlling the speed. This will all be incorperated in the final design.

Posted: Tue Mar 01, 2011 7:46 pm
by Gun Freak
Little update, I got a bunch of brass fittings for the final version, but it is still having feeding issues. I have to shake it after each shot to get a new bb in the breech. But there is another issue... a new bb is being sealed in the detent too quickly after the bb before it shoots, so I'll pull the trigger, there is a slight delay, then a rapid fire of bbs... how can I fix this? I know one solution is lowering the amount of air going in, but is there anything else?