Firewad 3D-CAPA Airsoft Pistol

Hello, I'm Firewad, and this is my 3D-CAPA Project.

The Firewad 3D-CAPA project started in 2025 as a question: how much of an airsoft Hi-CAPA pistol can be 3D printed? Over 1 year of painstaking development later, the answer is the Firewad 3D-CAPA: a near-fully 3D-printable GBB airsoft pistol based on the Hi-CAPA system. This unlocks a new world of possibilities; for example, you could build a 3D CAPA from spare HI-CAPA parts, revive a boneyard Hi-CAPA, or build a 3DCAPA entirely from scratch!

When designing this project, I wanted it to be 3 things: durable, high performance, and easy to build. I achieved this through some unique features in my design: a unique TDC hop-up and slide design has been used to improve performance and reliability, many parts have been thickened and optimised for 3D printing to maximise durability, and the assembly process has been simplified to make it easier to build and maintain. These design choices and many others have enabled the 3D-CAPA to offer performance and features similar to the Hi-CAPA, despite being fully 3D-printed.

Link to full information and assembly instructions: https://docs.google.com/document/d/1Sc-QUix0Q08mCW3vwT5wOBLv1ZRMmkyUWrveP8JwSQE/edit?usp=sharing

Read fully before starting this project.

I am actively developing and supporting the project with more variants (such as the 4.3 version) and features to be released in future updates.

For technical support or questions, join my Discord server and ask there: https://discord.gg/B5KFRRkb8R

Despite designing it to be easier to build, it's still a challenging build project and is not recommended for beginners new to airsoft or 3D printing.
Key Features:

Gas-Blowback: Full slide travel with a similar level of gas efficiency
TM Spec: Compatible with the massive ecosystem of Hicapa parts
Functional Slide Catch: Slide locks back when the magazine is empty
Functional Grip Safety: Has a beaver-tail grip safety similar to the Hi-CAPA
TDC Hop-Up: Precise hop adjustment and easy access to the adjustment screw (also compatible with aftermarket Hop-ups)
Textured Grip: Grip can be printed with the fuzzy skin modifier for extra hold
Ultra Lightweight Slide: Snappy and fast recoil
Two Slide Options: For a slide with iron sights or RMR included
Threaded Barrel Option: To mount a tracer unit or mock suppressor
20mm Lower Rail: To mount flashlights or other tactical accessories

Tech Specs:

Length: 222 mm
Weight:
Inner Barrel Length: up to 113 mm
Power source: HFC134a, Green gas (HPA possible under 110 PSI)
Firing modes: Semi-only
Magazine Compatibility: Hi-Capa magazines from Tokyo Marui, WE (other brands are unconfirmed)
FPS: ~280 FPS with green gas and 0.25g BBs

3D printing settings
I highly recommend printing from the 3mf file and using BambuSlicer (for Bambu printers) or OrcaSlicer (for other printers). The orientation, supports, and print settings have all been set up in the 3mf file. You will only need to arrange the parts yourself; the number of parts per plate will depend on how confident you are in your printer.

Recommended Filament: PLA+

Possible Filaments: PLA, PETG, PETG-CF, PA-CF

Recommended settings:
Nozzle size: 0.4mm
Layer height: 0.20mm or less
Wall thickness: 8
Infill: 100%
Support type: Tree