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Posted: Mon Jul 12, 2010 1:24 pm
by POLAND_SPUD
giving this another go
even 6mm calibre gun would be ok... mine has way more power than I thought I could get

Posted: Mon Jul 12, 2010 2:26 pm
by jackssmirkingrevenge
The question is, spring loaded tube magazine, or a vortex/cloud style chamber...

Posted: Mon Jul 12, 2010 2:32 pm
by jakethebeast
spring loaded magazine sounds better :D

Posted: Mon Jul 12, 2010 2:36 pm
by jackssmirkingrevenge
True, but you're limited to a single stack for the sake of reliability, and with airsoft you're only getting 10BBs ever 6cm.

Posted: Mon Jul 12, 2010 4:10 pm
by jakethebeast
hmm thats right, also you can make a blow forward bolt and magazine fet bbs, just buy cheap airsoft magazine

Posted: Mon Jul 12, 2010 4:10 pm
by POLAND_SPUD
with airsoft you're only getting 10BBs ever 6cm
not if you are using tubing with ID of, let say, 8mm

since hijacking threads has become a sort of tradition I decided to post a few pics taken today

lol let's face it.... reliability is the only thing that these things lack... I guess this vid illustrates it quite well
[youtube][/youtube]if you can find a way to make them 100% reliable then I'll start worshipping you

no, I am not talking about foot fetishes, BSDM and stuff like that

Posted: Mon Jul 12, 2010 5:44 pm
by jackssmirkingrevenge
I do admit to a penchant for questionable activities, but only involving the opposite sex ;p
POLAND_SPUD wrote:if you can find a way to make them 100% reliable then I'll start worshipping you
How about you make one decent video. Just one.

And it seems I no longer have the monopoly on maszyny wzdęcia :D

Seriously though, I think the standard vortex block is fairly reliable. Remember this?

[youtube][/youtube]

No feeding issues whatsoever. The problem with vortexes and clouds though is that they need a minimum flow rate to agitate the BBs sufficiently, so the rate of fire has a lower limit and I don't think semi-auto would be practical.

Posted: Mon Jul 12, 2010 7:01 pm
by POLAND_SPUD
How about you make one decent video. Just one
lol soooorry... me was trying hard :D
No feeding issues whatsoever. The problem with vortexes and clouds though is that they need a minimum flow rate to agitate the BBs sufficiently, so the rate of fire has a lower limit and I don't think semi-auto would be practical
well I am actually a bit surprised that something so crude works so well... but it would be cool if I could achieve 100% reliability with heavier ammo than 0.12g

you are right about the flow... when I replaced the 3 way with a blowgun feeding was much better... unfortunately, the ROF was much higher

maybe it is just a matter of using a large enough chamber and/or dividing it into two compartments - one for ammo and one that stores air that will push the next round to the detent as soon as the gun fires

anyway now that I think of it it might be a better idea to build a simple tube magazine :?

Posted: Tue Jul 13, 2010 12:27 am
by jackssmirkingrevenge
POLAND_SPUD wrote:lol soooorry... me was trying hard :D



Not hard enough, are cameras rare and expensive in Poland :D
anyway now that I think of it it might be a better idea to build a simple tube magazine :?
The more you think about it, the more it seems like the best solution. I wonder what the pressure rating of an airsoft magazine is...

edit: Fate seems to have delivered a sign, I found on my desk this morning a mud encrusted spent 0.303 cartridge, seems one of the operators dug it up while doing some gardening :D hmmm...

Posted: Tue Jul 13, 2010 4:42 am
by al-xg
The cheap airsoft magazines I've seen are two halves that just have a U shaped or spiral groove.

Ah, well I took one apart:
Image

I would be nice to replicate that with 8mm ID tube, maybe by heating and bending with sand then casting in epoxy...

Posted: Tue Jul 13, 2010 5:19 am
by Technician1002
For bending tubing, they make steel springs that can be placed inside or outside the tube to prevent tubing collapse in the bends. Sand works somewhat but still permits some flattening in bends. A good steel spring tied to a rope can be pulled into place, the bend made, then pulled to the next bend, and repeated as needed to finish the magazine.

Posted: Tue Jul 13, 2010 5:32 am
by al-xg
I have a few of those for larger coper pipes but sadly no 8mm ones...

Mmm bicycle brake line ? Maybe if the tube is anealed first.

Posted: Tue Jul 13, 2010 5:55 am
by jackssmirkingrevenge
Interesting thought. You can get 10mm O/D 8.6mm I/D copper tubing for about $6 a metre - for 6mm projectiles, you'd have enough tolerance to be able to bend it without worrying about kinking the tube beyond 6mm, and with a claimed 8000 psi burst pressure, that's 10 times the pressure I'd be working at, so no need for epoxy sarcophagii ;)

Finding a spring that long might be a slight issue though...

Posted: Tue Jul 13, 2010 8:11 am
by inonickname
Simple..make some. Spiral some music wire into shape and stress relieve it.

Posted: Tue Jul 13, 2010 8:12 am
by POLAND_SPUD
I think that spring isn't needed... air will work just fine
I tested a short length of 6mm ID tubing and it feed reliably... Of course it didn't work too good since there was no gap around the bbs and no ports cut in the tubing directly at the detent

It was the true farting machine (it really sounded like a farting machine and power was similar to what you could achieve with your own a### if you swallow a handful of bbs :wink: )