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projectile/ trigger system and chamber all in one.

Posted: Fri Dec 03, 2010 12:33 am
by novak
well i've been trying to think off the most simple way to make the fastest valve. which got me to thinking of just using the projectile as a plug which is locked in by a pin.

by drilling a small hole in the barrel for the pin to go through and lock into the projectile. using o rings wrapped tight to seal the barrel.

pressure loss by a very small hole would be minimal.

this system also could be worked into a cartridge style depending on size. or just a simple single shot pre made device.

Posted: Fri Dec 03, 2010 12:43 am
by PVC Arsenal 17
No reason why it wouldn't work, but I'd consider putting the o-ring after the pin (to prevent tearing them if you intend to reuse these projectiles) and simply seal the pin mechanism.

Posted: Fri Dec 03, 2010 12:45 am
by novak
o rings are cheap anyway so im not worried about them. i'll need to make a test gun and see how it all goes first

Posted: Fri Dec 03, 2010 12:55 am
by ThornsofTime
Sorry im not an expert linker like Sir.JSR, however, do a quick forums search for "VALVELESS PNEUMATIC". There is a LOT of thought/discussions behind this concept that may be of use to you if you decide to progress with the idea.

Posted: Fri Dec 03, 2010 12:58 am
by jackssmirkingrevenge

Posted: Fri Dec 03, 2010 1:07 am
by novak
Image

thanks to jsr for this one aswell lol


i'd make it to shot 3/4 projectiles. im in australia so i cant get hold off pellets or anything crazy.

Posted: Fri Dec 03, 2010 1:12 am
by ThornsofTime
Yeah, I knew JSR would come save the day. Funny how much stuff you learn by dedicated trolling... and the things you find yourself thinking about on the drive to work... I rarely get punched in before wishing I was back home in the shop....

Posted: Fri Dec 03, 2010 1:32 am
by jackssmirkingrevenge
The problem with this sort of system is that you're greatly limited to certain types of projectiles. If you substitute the seal and detent for a burst disk however, you can get practically identical performance and shoot whatever fits in the barrel, something like this.

Posted: Fri Dec 03, 2010 1:59 am
by POLAND_SPUD
The problem with this sort of system is that you're greatly limited to certain types of projectiles
let's make it clear that you're not limited to spherical ammo only

What Jsr wanted to say is that you can't shoot sand, water, vegetables and stuff like that... well not unless you sabot them

Posted: Fri Dec 03, 2010 2:06 am
by jackssmirkingrevenge
POLAND_SPUD wrote:well not unless you sabot them
Some ideas along those lines in this thread

Image

Image

The concept is sound, but restraining the forces involved requires some pretty substantial construction

Posted: Fri Dec 03, 2010 2:16 am
by POLAND_SPUD
The concept is sound, but restraining the forces involved requires some pretty substantial construction
yeah, but the gun can be as loud as a bow... well, at least that's what BTB's experiments suggest

Posted: Fri Dec 03, 2010 2:21 am
by jackssmirkingrevenge
double post :?

Posted: Fri Dec 03, 2010 3:03 am
by jackssmirkingrevenge
POLAND_SPUD wrote:yeah, but the gun can be as loud as a bow...
or quieter ;)

[youtube][/youtube]

[youtube][/youtube]

I like psycix's "air bumper" suggestion, it's probably the best way to stop the thing destroying itself:

Image

Posted: Fri Dec 03, 2010 3:23 am
by novak
POLAND_SPUD wrote:
The problem with this sort of system is that you're greatly limited to certain types of projectiles
let's make it clear that you're not limited to spherical ammo only

What Jsr wanted to say is that you can't shoot sand, water, vegetables and stuff like that... well not unless you sabot them

im not fussed by that and i dont care how loud it is.

and i want simple. the only hard part is working the trigger into a stock. besides that its pretty much a combustion cannon with a little hole in the barrel. if i can get it to seal it'll work great imo

Posted: Fri Dec 03, 2010 4:32 am
by jackssmirkingrevenge
novak wrote:im not fussed by that and i dont care how loud it is.
The point was that to shoot irregular objects, you'd need a sabot, and to avoid making new sabots every time, you might as well catch it, and one of the advantages of doing that is retaining the propellant gas which cuts down on noise.