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6mm pistol design 2.1

Posted: Sat Feb 13, 2010 4:12 pm
by Demon
I know that i am pprogressing kinda slowly as i am in school and busy, but i had various moments to think of the design. So i realised that i was not able to machine an hammer valve without too much big leaks from the hammer rod connected to the outside ...

So its piston time!

The new valve slightly modified the design for the better as now the wooden stock covers the end, thus making a stronger structural point (wich i didn't knew how to hold the barrel on the v 1.0 ) for the upper part.

My only concern is the trigger :

Will the speed of activation of the trigger modify the opening speed of the valve, and the ammo velocity?

I certainly dont want to be able to empty the air tank without shooting by fiddling on the trigger ...

So ?

Re: 6mm pistol design 2.0

Posted: Sat Feb 13, 2010 8:50 pm
by Gippeto
Demon wrote: My only concern is the trigger :

Will the speed of activation of the trigger modify the opening speed of the valve, and the ammo velocity?

Yes. Inconsistant as all heck.

Try again...don't give up. :)

Posted: Sun Feb 14, 2010 10:26 am
by Demon
This is what i thought too...

Then, what about this design?

When you press the trigger, it releases the seal wich moves back because of the seal that goes in the sealing tube, giving it enough inertia to move back far enough, and most importantly, consistently .

The spring will have to be strong enough to squish the sealing face, enabling the trigger to catch the "sealing bolt" (in red) .

Posted: Sun Feb 14, 2010 6:27 pm
by Gippeto
You're going to have trouble getting a reliable seal that works for any length of time.

Change it to a probe with an oring, which fits inside the port, and slides clear when released. Silicone (divers) grease will be your lubricant of choice for that oring.

Then I think you're good to go.

Posted: Tue Feb 16, 2010 6:05 pm
by Demon
Well, sadly, its easier to say then to do :cry:
But i am working hard ...

And i have a question over pressure safety :

Can a aluminium over aluminium press fit (hammered in) with metal epoxy hold to 200 psi ?

Posted: Fri Feb 19, 2010 6:08 pm
by Demon
I received the barrel (6.03 madbull barrel and .43 g bb's ) a few hours ago and i tested it on my sprinkler valve potato canon (with an adapter)
and it was pretty impressive...

At only 400 fps, i shot a wood piece and got enough penetration to get the bb stuck at 450 fps i dented a 2/3 of a millimeter steel plate of 3-4 mm :twisted:

The final version (with much higher psi) would shoot at 520 fps ... and be portable

When i shot pvc, the bb was in very tiny fragments .