Hello, this is my first big project in CAD/3D Printing so every bit of advice is greatly appreceated.
My general idea is a GBB, that can be powered with HPA, still utilising GBB mags.
The HPA line is either beeing routed around the bolt, through it and the bolt gets a slit in the center, or behind it, next to the stock.
Switching from HPA to GBB is done by changing the Bolt (easier than only the nozzle), where the (probably custom) nozzle takes the propellant from the top rather than the bottom.
Because of that way of changing i would prefer routing the HPA line on the side or at the stock, but am open to suggestions.
For the FCG i wanted to base on a standard VFC spec M4 trigger group and the hammer drags the dotted part forward when engaging, to hit a standard gbb mag valve in the pink area, to release the HPA, while also hitting the mag, holding onto the standard way of operation.
Issues i forsee in this part, the safety might be in the way of the new connector, so i will have to find a way around that.
The magazine is going to be VFC G3, first, cause i already have them, second because they have that metal connector between valve and hammer, that springs to the side, allowing me to use HPA without the Gas valve beeing hit.
General Design aspects:
- Pistol Grip is M4/AR15 spec
- stock mount will be picatinny or other standard modular stock base
- charging handle will be on the side, similar to FAL or BRN 180 gen1/2, so left or right, not like an M4
Questions i still have open:
- How thick do aluminium walls need to be to handle atleast 11Bar/150PSI
- How do i go about connecting the HPA line from lower to upper receiver, as the design is completely new, creative ideas are welcome
- what standardized parts can be utilized to reduce cost and designing time