Scorpion Piston - TAC41 + Spring Guide

The new Stalker Scorpion piston for the TAC41!

Key features:

• Modular piston with adjustable weight (from ~65 to 148 grams)
• Silences your TAC41
• Increases joule/FPS consistency
• Adjustable airbrakes for optimal fine-tuning
• Optional short-stroke setup for your TAC41 for faster reloads and a shorter bolt pull

The piston includes 2 adjustable airbrakes for optimal fine-tuning based on your setup.

• 1 short 3.80 mm airbrake (optimal for 2J and 3J~ or higher upgrades).
• 1 long 3.80 mm airbrake (optimal for 2J~ or lower upgrades).

The included airbrakes are designed to work with the standard TAC41 cylinder head. If you are using the GBB hop unit or the TAC41 Kraken, you must purchase the thicker airbrakes.

A High Joule cup (shiny) is included for higher joule output and a lighter bolt pull.
Use lubricant for perfect results; we recommend motor oil, silicone grease, or similar. As a reference, a Rapax Lightpull Blue 2J+ spring achieves approximately 2.2–2.3~ joules in a TAC41 with a Stalker TAC41 cylinder and a 420 mm inner barrel. The original cylinder will produce lower joules. Results may vary depending on the cylinder used.

Golden installation rules

• Always apply a drop of oil or silicone grease to the edge of the head to achieve optimal joules.
• For 2.3J setups, we recommend starting with the short airbrake fully unscrewed.
  For 2.8J+ setups, we recommend starting with the short airbrake fully screwed in.
• Always set your hop-up correctly for your desired BB weight and adjust it to shoot straight.
• More joules = shorter airbrake
• Less joules = longer airbrake
• Choose your airbrake and start low, then increase (unscrew) gradually until the setup is quiet.
• When you begin to lose joules, you know you are just past the perfect airbrake position. Screw it back in slightly to regain joules and achieve the quietest setup.

Proper setups require adjustable airbrakes because too many parts in your rifle can change the piston acceleration speed. Piston weight, spring power, bucking hardness, barrel length, etc. We also recommend purchasing some spring guide spacers to fine-tune piston weight and spring joules.

Included in this kit:

• 1x Stalker stainless steel spring guide (with engraved Stalker logo)
• 1x High Joule piston head (shiny)
  
• 1x Aluminum piston head
• 1x Stainless steel piston head
• 5x Aluminum weights
• 4x Stainless steel weights
• Sear and end cap made of stainless steel (rainbow finish)
• 2 adjustable airbrakes (long and short)
• 1x nut to lock the airbrake setting
• 10 O-rings to place between weights or the head to prevent weights from loosening
• Front and rear POM guide rings

Detailed information:

The Scorpion piston is a unique concept where 6 weights form the actual body. Since the piston itself is made up of these weights, it is also possible to extend the piston with additional weights (short-stroke), which reduces your cylinder volume and joule output, but shortens the bolt pull of your TAC41 with each added weight—at the cost of joule output, which can be compensated with a stronger spring.

The piston comes with 9 body weights that are interchangeable to perfectly configure your TAC41.

• 5 black anodized aluminum body weights, each piece weighs: 3 grams
• 4 polished stainless steel body weights, each piece weighs: 11 grams

In addition, the piston also includes 2 head weight versions.

• 1x Black anodized aluminum head weighing: 7 grams
• 1x Polished stainless steel head weighing: 17 grams

List of 6-piece configurations:
(The fifth stainless steel mid-section weight is sold separately if you wish to use full heavy steel configurations)

• TAC41 Scorpion 62g (1 aluminum head, 5 aluminum mid-sections)
• TAC41 Scorpion 76g (1 aluminum head, 1 steel mid-section, 4 aluminum mid-sections)
• TAC41 Scorpion 80g (1 steel head, 5 aluminum mid-sections)
• TAC41 Scorpion 89g (1 aluminum head, 2 steel mid-sections, 3 aluminum mid-sections)
• TAC41 Scorpion 93g (1 steel head, 1 steel mid-section, 4 aluminum mid-sections)
• TAC41 Scorpion 102g (1 aluminum head, 3 steel mid-sections, 2 aluminum mid-sections)
• TAC41 Scorpion 107g (1 steel head, 2 steel mid-sections, 3 aluminum mid-sections)
• TAC41 Scorpion 115g (1 aluminum head, 4 steel mid-sections, 1 aluminum mid-section)
• TAC41 Scorpion 119g (1 steel head, 3 steel mid-sections, 2 aluminum mid-sections)
• TAC41 Scorpion 128g (1 aluminum head, 5 steel mid-sections)
• TAC41 Scorpion 133g (1 steel head, 4 steel mid-sections, 1 aluminum mid-section)
• TAC41 Scorpion 145g (1 steel head, 5 steel mid-sections)
  This configuration requires a fifth stainless steel mid-section, sold separately.

Both airbrakes are secured with a nut under the cup against the piston head to keep them in place after adjustment. The adjustable airbrake is designed to control piston speed at the end of its stroke, reduce cylinder air release time, and minimize piston impact noise when it hits the head. A Sorbo pad on the head can still be used with this piston.

Basically, whether you prefer a plug-and-play piston or you are an expert fine-tuning piston weights and airbrakes for maximum performance, the Stalker Scorpion is your best friend.

If you have any issues or questions about this or other Stalker products, visit our Stalker owners group on Facebook here:

https://www.facebook.com/groups/329589544772075/

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For more information about Stalker products, tech guides, and builds, visit: www.stalkerairsoft.com