No-seal pneumatic cartridge.

[fractal]

-RED: Seal

-GREEN: Firing pin

-BLACK: Projectile

The bullet seals the barrel. Air can't get behind the bullet and push it down the barrel. When something hits the firing pin it moves the bullet a little bit forward, but enough to the pressurized air get behind the bullet and shoot. :bounce:

[mobile chernobyl]

http://www.spudfiles.com/pneumatic-cann ... 58-15.html

[Technician1002]

The design works well but manufacturing the projectiles takes lots of effort for single use. An alternate design shoots a similar designed valve core to the rear for re-use, while permitting much larger selection of projectiles. Look in my sig for examples.

[Gleedaniel13]

If the the effort can lead to good results then why not try?

[mobile chernobyl]

The design certainly has it's benefits - one of the most notable will be consistency.

A professor was leading a project for Engineering seniors in my school - and I asked them why they picked a similar design for testing - repeatability was their claim. They were designing a kinetic energy delivery system to imitate concrete debris being blasted from a wall at a soldier behind it - the end product being used for the testing and qualification of body armor.

It makes sense - given that the projectiles mass can be fine tuned easily - and the seals will always be in the same condition: "new". Therefore, give chamber pressure and temperature you should be able to depend upon a consistent muzzle energy.

[jackssmirkingrevenge]

Typically, someone already patented it: http://www.spudfiles.com/spud-cannon-re ... ss#p146694