Sirius BullPup

Maximum performance. Minimal footprint.

Sirius is a compact high-performance HPA platform engineered for aggressive CQB environments.

Built around a bullpup architecture, the platform relocates the action behind the trigger, delivering rifle-level performance in a significantly shorter overall length.

This results in a highly maneuverable and space-efficient configuration, ideal for tight indoor scenarios while maintaining compatibility with standard M4 magazines and high-performance HPA systems.

Required hardware (not included)

This listing includes the STL file package only. You must source and assemble commercial airsoft components and hardware before the platform is field-ready.

HPA engine

• PolarStar F2™ or Jack™.

Barrel / hop-up kit

• Standard M4 hop-up unit (e.g. Prowin, Maxx Model, or PolarStar hop-up interface).
• Precision inner barrel suited to your configuration (280 mm recommended for Sirius bullpup).
• Standard M4/AEG adjustable trigger blade.

Fasteners & inserts

• M3 heat-set brass threaded inserts.
• M3 machine screws (typically 5–15 mm depending on assembly step).
• M5 screw and nut where specified for stock and adapter interfaces.

Using a different HPA engine or hop-up setup?

Platform geometry can often be adapted. Open a request in our Discord community with your engine model, hop-up unit, and barrel length — we will help you find the correct revision or a community-tested solution.

Coming soon: support for Wolverine and Blackdraft Innovations engines.

License

Files are licensed for personal use only. Commercial use, resale, redistribution, or sharing of the files is strictly prohibited.