Syringe attached to a flexible tube and the air will push  up a preload tube of propellant into the cavity then the nozzle is friction plugged.




I am currently working with an engineer to figure out the right nozzle size and wall thickness so it doesn’t grenade. The first simulation grenaded so we beefed up the wall thickness, added support columns, opened the nozzle by x2.5 and reduced the volume to cut down on propellant volume capacity. The concept is proven given the extensive data in the patent, it’s just about figuring out a way to apply that to modern manufacturing techniques and materials.

Here is the new design waiting for trails in the simulator. You can see a drastic change in strength and support

New book is out now

Link to book for those interested

Ordered. Thanks and keep up the good work.

Means a lot mate !

Got some printed rocket in to test the concept

Very interested in seeing how these go.  What powder are you planning on starting with, and what pressures are you expecting?

How much did that cost? Never had a 3DP metal part made.

I bought 20N29 50BMg powder to keep the pressure as low as possible but the simulations were running US 869 powder at between 3k-23k  PSI depending on how you calculate it

20k PSI is a LOT of variation.

Godspeed.

https://www.ar15.com/forums/t_1_5/2718674_High-definition-footage-of-a-Gyrojet-pistol-.html

It’s just hard to calculate when there a lot of variables involved that differ from regular firearms and regular rockets . When we get some test data we’ll have a better image to calculate the PSI pressure