SpudFiles

Technician1002 wrote:Due to the physics involved in a hybrid, air is too dense to provide velocities very much above the speed of sound.

HACKERZLORD007 wrote:How much pressure approximately does a hybrid cannon generate?

and is it possible to build a pneumatic cannon which can beat a hybrid cannon in performance and muzzle velocity?

HACKERZLORD007 wrote:I was wondering if there was any way to build a pneumatic gun which could either match the performance and muzzle velocity of a hybrid gun

Technician1002 wrote:Due to the physics involved in a hybrid, air is too dense to provide velocities very much above the speed of sound.

With heavy dense projectiles air does fine as the heat of combustion is relatively short in duration.

With lighter projectiles, an air cannon won't match a hybrid.

saefroch wrote:It depends on what the construction of both is, and what mix the hybrid is running at as compared to the pressure the pneumatic is running at. But... if I were to have two identical builds, and run them as close to failure as I felt comfortable, the hybrid would best the pneumatic.

If you're trying to beat out a hybrid with a pneumatic, we may or may not be able to help. We'd need more information.

jimmy101 wrote: Though given the temperature dependence of the SOS (and the near independence of the SOS on density), the SOS inside a hybrid is a lot higher than ~300m/s (1100ft/sec)

SOS in air at 700C is about 2x that in air at 20C.

jackssmirkingrevenge wrote:

HACKERZLORD007 wrote: and is it possible to build a pneumatic cannon which can beat a hybrid cannon in performance and muzzle velocity?

How long is a piece of string?

You can always build a more powerful pneumatic, but chances are it will be bigger and more complex than the equivalent hybrid - and if you want high supersonic velocity, pneumatics are limited by physics well below 2000 feet per second.

HACKERZLORD007 wrote:is it possible to build a pneumatic cannon which can beat a hybrid cannon in performance and muzzle velocity?

HACKERZLORD007 wrote: "how do i increase the velocity of my pneumatic gun....it has a 30 cubic inch chamber.....do i increase the chamber volume or do i use higher pressure....(current pressure: 100-150 due to 12 v compressor)????

MrCrowley wrote: Usually with pneumatics, increasing the barrel length or pressure would increase velocity.

Download GGDT (google search for it if you don't know what it is) and plug your cannon's parameters in and see what it says. It's a program for modelling cannons and is dead simple to use. Just read the FAQs on the website.

HACKERZLORD007 wrote:just wanted to confirm how i could increase the muzzle velocity of my pneumatic rifle ????

Should i try increasing the chamber volume or should i try increasing the chamber pressure???
(Currently running 30 cubic inches at 150 psi)

Help Needed......thnx!!!!
CHEERS

Tobin wrote: What is most efficient depends on the barrel. How long barrel u have and what is the diameter at the barrel?

Gun Freak wrote:Yeah we need more specfications like barrel length, chamber length/diameter, valve...

saefroch wrote:Both will do it, but I'd suggest increasing pressure since that's usually easier, but not if you'd be pushing the pressure rating on components.

jackssmirkingrevenge wrote:Increasing chamber volume is effective up to a point, after that could can double the volume and only get a 1% increase in velocity. Increasing pressure on the other hand should give a roughly linear increase in power.

Download Gas Gun Design Tool and have a play before cutting.

Tobin wrote: Then increased chambervolume wont make any noticable difference

HACKERZLORD007 wrote: I recently started spudding as a hobby and i started off by making a pneumatic spud. I made one with totally galvanized fittings and pipes. My gun has a 30 cubic inch tank and a half inch bore! Well i was wondering how i can improve the range and velocity of my air gun? Should i use a bigger chamber or should i increase the pressure? (Current Pressure - 150 psi)?? I can shoot a double a battery a good 70-100 on abt 150-160 psi but i want like about 200 mts range and abt 500+ fps...so wht shd i do to improve my gun performance to this standards???? NEED HELP!!!

jackssmirkingrevenge wrote:Again: http://www.spudfiles.com/forums/viewtop ... tml#320623

MrCrowley wrote:HACKERZLORD007,

PM me. Not sure why you posted this twice (as well as PMing me and asking me the same question).

Do your own research, you have been given a wealth of information from several members, more than enough to hit the ground running. I don't want to see you asking this question again.

Labtecpower wrote:I want to make a large hybrid, so I wanted to practice some with fueling and igniting.
I made a crude and ugly version of the hybrids JSR makes.

DYI wrote:ITWOSY: ten hours of work and five pounds of insulation later, the capacitor bank can now be charged to ~14kJ at 24kV without any hissing, arcing, or destruction of multimeters. How well the rest of the equipment in the circuit fares at these discharge energies will be determined in the very near future...