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Silent System( now broken by dieseling!)

Posted: Wed Nov 25, 2009 5:21 pm
by Brian the brain
Just something I have been wanting to try for a long time.

I tried this system before on my " push botton valve" experiment.It needed more flow..

Take a barrel, shove in a rubber " sabot" and put a reducer on the muzzle.

The sabot can now push an arrow, but it cannot exit the barrel.A drilled out center point helps to keep the arrow aligned and steady.
This causes the gas to be trapped.

Of course..I made it so that not doesn't seal 100% ..the air bleeds out slowly..resulting in a silent shot.
An arrow gives better penetration while the sabot gives it more force.. :D

Unfortunately, threading a reducer into the muzzle made the barrel sleeve turn over it's foam tape insides and droop even more, but this is just a prototype,
I will replace it by a shiny new barrel all together
*( " I will replace...")* :D

I will also drill ports in front of the sabot to enable it to push out the air in front faster.Next try the system will be removable, so I can still fire marbles and 16 mm ball bearings if I choose to.

The arrow ( or airrow..) got launched in complete silence, apart from the impact, wich was not too loud and most importantly, doesn't even sound like a shot.

Damage was done at under 300 psi.The gun could take a lot more..
The target is 4cm thick quality hardwood, shot at a 90 degree angle to the fibers. ( hardest to do)
So much for reusable arrows..I can't get it out...

Posted: Wed Nov 25, 2009 5:42 pm
by jrrdw
Try and get a video with good sound posted if you can. Nice work.

Posted: Wed Nov 25, 2009 5:45 pm
by Brian the brain
uh-huh...

Like that ever worked before... :D

I'll spell it for you..

:roll:

POK ( impact)
Pffffffffffff

That's it..

This is easier than a silencer too.
Anyone can build this!

Posted: Wed Nov 25, 2009 7:02 pm
by roboman
That's incredible!

Correct me if I'm wrong, but this gun operates something like a pop-off/burst disk (pressure builds up, and at a certain point, it lets go)?

Posted: Wed Nov 25, 2009 9:10 pm
by Ragnarok
Just imagine what a longer barrel and arrow will do at 40 bar.
Smash the sabot catcher off the end of the barrel?

I know there have been various silent firearms based around the same "trapped gas" technique, but the idea of having high velocity and somewhat weighty pieces smashing around inside a launcher has never appealed.

(Pistons being an exception, they seldom have much acceleration distance)

Posted: Wed Nov 25, 2009 9:22 pm
by VH_man
so wait... Theres a Sabot that always remains inside the cannon?

I'm assuming it fires somewhat like the Msp Silent Pistol. If so, very sweet. And a little scary. In a good way.

Posted: Wed Nov 25, 2009 9:28 pm
by JDP12
Operates almost exactly like the bs-1 tishina...

I've thought about something like that before for paintball, this may be the motivation to work on it again!

Posted: Wed Nov 25, 2009 11:19 pm
by jackssmirkingrevenge
ilovetoblowthingsup wrote:Operates almost exactly like the bs-1 tishina...
The idea is certainly not new but good to see it implemented :) and since it's soooo silent, he cannot use the neighbours as an excuse for not making a video :D

I'm guessing it's pretty much identical to the SP-4 cartridge concept using a cylindrical projectile driven by a piston?

Image

unfired cartridge

Image

firing

Image

piston jammed against cartridge, projectile fired.

Posted: Wed Nov 25, 2009 11:49 pm
by JDP12
Yup.. Dang I wish I had more money to do all the projects I want to

Posted: Thu Nov 26, 2009 12:54 am
by jackssmirkingrevenge
ilovetoblowthingsup wrote:Yup.. Dang I wish I had more money to do all the projects I want to
This can be done pretty cheaply as an attachment for a "standard" launcher, I like the rubber sabot idea, heavy but it helps to soften the impact. If you carve out a small space in the centre of the piston, you wouldn't be limited to cylindrical projectiles either, though accuracy would probably suffer.

Posted: Thu Nov 26, 2009 3:30 am
by POLAND_SPUD
if you carve out a small space in the centre of the piston, you wouldn't be limited to cylindrical projectiles either
already suggested :D

accuracy issues probably could be solved by adding a short length of small bore barrel at the muzzle. It would be the best to have a short tapered section of the barrel facing the piston so that the projectile could get in the barrel

Posted: Thu Nov 26, 2009 4:44 am
by jackssmirkingrevenge
POLAND_SPUD wrote:accuracy issues probably could be solved by adding a short length of small bore barrel at the muzzle. It would be the best to have a short tapered section of the barrel facing the piston so that the projectile could get in the barrel
Precisely what I was thinking ;) still, the projectile cannot be too off-centre, otherwise you'll fire the barrel off as well :D

Posted: Thu Nov 26, 2009 6:25 am
by Major Collins
nowwww just make some shotgun ammo and it really will be a sawn off : ) and the idea of a silenced sawn off .... lol

Posted: Thu Nov 26, 2009 6:53 am
by jrrdw
Brian the brain wrote:uh-huh...

Like that ever worked before... :D

I'll spell it for you..

:roll:

POK ( impact)
Pffffffffffff

That's it..

This is easier than a silencer too.
Anyone can build this!
WOW :shock: ...That's got to be the quitest video I never heard, sweet!

Posted: Thu Nov 26, 2009 7:55 am
by Jack_Hogg
This is a very good way of making dart barrels :D
I also thought of this concept, but thought it would blow off
the reducer by kinetic energy of the "pusher/sabbot/piston"
Well, I am really thinking of making this too of my 22mm
barrel. It would be very silent. So I would have a very
loud shotgun big smoothbore barrel and a super silent dart
barrel. This is awsome :D Nice build :wink: