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Kit de alineacion para SR25 - Polarstar F2 & Alpha 2026
Kit de alineacion para SR25 - Polarstar F2 & Alpha 2026

PolarStar F2 + Silent Industries ALPHA 2026 · Alignment Kit V2.1 · SR25 AEG HPA

23,00 €
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Version 2.1 of the hop-up alignment system, designed for SR25 AEG HPA replicas with a V2.5 gearbox.

This kit is designed to use the SR25-specific PolarStar F2 engine together with the Silent Industries ALPHA 2026 chamber. This new version of the chamber features an updated external geometry with sharper angles, requiring a locking and alignment system adapted to its design.

The kit keeps the PolarStar F2 nozzle centered relative to the chamber, helping to reduce lateral movement and improve feeding consistency in DMR-style HPA configurations.

Compatibility

Component Compatibility
HPA Engine PolarStar F2 specifically for SR25
Hop-up Chamber Silent Industries ALPHA 2026
Base Replica SR25 AEG
Gearbox V2.5 / Extended V2
Configuration HPA / DMR

Important: This version is designed specifically for the Silent Industries ALPHA 2026 chamber, with its updated external geometry and sharper angles. Compatibility with previous ALPHA chamber revisions should not be assumed.

Main Features

  • Design adapted to the geometry of the ALPHA 2026.
  • Upper cap with support areas adjusted to its sharper angles.
  • Precise alignment between the PolarStar F2 nozzle and the chamber.
  • Compatible with V2.5 gearboxes for SR25 platforms.
  • Rear reinforcement using an M5 screw.
  • Side routing for the HPA line.
  • Housing for M3 inserts.
  • Structure designed for DMR-style HPA configurations.

What the Kit Includes

  • Rear clip for mounting using the rear pin or fixed stock.
  • Alignment base specifically designed for the Silent Industries ALPHA 2026 chamber.
  • Housing for M3 inserts.
  • Side clip for HPA line routing.
  • Upper front locking cap adapted to the angles of the ALPHA 2026.
  • Rear plate with mounting point for an M5 screw.
  • Support elements to keep the nozzle and chamber position stable.

Installation and Adjustment

  1. Printing and Preparation
  • Print the parts with an infill between 65% and 80%.
  • Lightly sand the internal surfaces and contact areas.
  • Pay particular attention to the angled areas of the upper cap.
  • Remove any burrs that could prevent the ALPHA 2026 chamber from seating correctly.
  • If necessary, apply dry lubricant or wax to the sliding surfaces.
  1. Installation in the Replica
    • Place the base in the lower receiver of the SR25 replica.
    • Install the M3 inserts into the designated housings.
    • Install the Silent Industries ALPHA 2026 chamber together with the inner barrel.
    • Install the rear clip using the rear pin or stock mounting system.
    • Route the PolarStar F2 HPA line through the side clip.
  2. Nozzle Alignment
    • Check that the SR25-specific nozzle is centered with the chamber entrance.
    • Verify that the nozzle moves in and out without rubbing or lateral pressure.
    • Check that the upper cap angles make proper contact with the ALPHA 2026 chamber.
    • If there is lateral play, inspect the chamber seating and perform very light sanding if necessary.
  3. Final Securing
    • Install the rear plate and use an M5 screw with washer to increase rigidity.
    • Check that the inner barrel remains centered.
    • Install the magazine and perform feeding tests.
    • Adjust the hop-up and PolarStar F2 settings progressively.

Required Components (Not Included)

  • 4× M3 × 4.2 mm inserts
  • 4× M3 × 8 SHCS screws
  • 1× M5 screw
  • 1× M5 washer

Assembly Recommendations

  • Use the PolarStar F2 nozzle specifically designed for SR25.
  • Check the nozzle length before closing the replica.
  • Do not force the chamber against the nozzle.
  • Make sure the ALPHA 2026 chamber is fully seated against its angled supports.
  • Do not mix the upper cap from this version with parts designed for previous versions of the ALPHA chamber.
  • Verify compatibility between the lower receiver, V2.5 gearbox, and installed chamber.
  • Perform initial tests at low pressure and gradually increase the settings.

Lower Receiver Recommendations

A metal ICS lower receiver or a lower receiver with sufficient structural rigidity is recommended to prevent movement between the gearbox, chamber, and inner barrel.

If you prefer to print your own lower receiver, these Gearbox v2 Lower "Universal Lower" models may be useful:

  • Version 3
  • Version 4.2
  • Version 4.3 MTW

You can find them HERE.

Lower receiver compatibility should be checked according to the specific SR25 model, body manufacturer, and type of V2.5 gearbox installed.