/sci/ - Science & Math

[Anonymous No.5958854]

I create potato guns and am interested in making an air gun that truly rivals firearms using only air pressure. Yes, I know the sound barrier cannot be broken if you assume temperature to be constant, but a compressed gas heats up and sound travels faster in a heated gas.

Actual question: Does a cone shape plunger make the projectile go faster if both plungers travel at the same velocity, and assuming the air volume behind the projectile is the same, takes the same amount of time etc.


I think so since the velocity of the air that has to evacuate must increase for the cone, so it would make a superior air gun.

[Anonymous No.5958861]

The latter is displacing more volume, unless you shorten the cylindrical/rectangular piston.

[Anonymous No.5958884]

>>5958861
I'm assuming the displaced volume is the same.
The pistons travel the same distance, same speed profile (propelled by reserve air tank), air in the cone has to travel further, and therefore faster, to exit the space.
Like a 1" x 16" barrel that evacuated a projectile in one second would make it faster than a 4" x 4" tank that propelled the exact same projectile.

I am having a terrible time trying to see how this could be better. NASA uses it on their air guns but contemporary nail guns do not, yet they are more concerned with momentum post impact than barrel velocity.

[Anonymous No.5958904]

>>5958854
You will probably need something like this to really rival a conventional firearm.

[Anonymous No.5958905]

>>5958854
>>I know the sound barrier cannot be broken
wrong it can, use a convergent-divergent nozzle

PROTIP: make a light gas gun, use hydrogen gas, make sure to PURGE OF OXYGEN!