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PolarStar Airsoft JACK Electro-Pneumatic Gearbox Conversion Kit (Model: M249)

ID: 54163 (GB-PS-Jack-SJMG-M249)
10000748
PolarStar Airsoft JACK Electro-Pneumatic Gearbox Conversion Kit (Model: M249)
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PolarStar

$333.50

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The JACK system was designed to answer the demand for an affordable, high performance HPA (High Pressure Air) conversion for AEG's. The system is a drop-in cylinder replacement that is universally compatible with a wide range of gearbox versions that have center-line nozzles.

Similar to its sister product, the F1, it replaces the original gearbox components with a programmable pneumatic system allowing for higher performance and greater reliability over a gear driven system. Although economically priced, JACK still retains the same performance and quality you have come to expect from PolarStar products.

JACK has only 1 moving part, the nozzle, which acts as its own poppet valve which is piloted by the solenoid. With the exception of the poppet being integral to the nozzle, the valve is similar to the poppet valve used in the previously released Fusion Engine and is what gives JACK its signature muzzle report. The system itself only has 6 parts and can be completely disassembled by hand in a matter of seconds so the system is very reliable and easy to maintain.

Just like all other PolarStar HPA conversions, JACK also allows for easy velocity adjustment. Using a standard M4 as an example, velocity can be adjusted from below 280fps and up to approximately 500fps with a .20g BB. This can be done simply by adjusting input pressure and poppet dwell to fine tune your rifles velocity in increments of just a few FPS at a time. Maximum velocity potential of the system will vary depending upon the barrels length and tightness of the bore. Longer and tighter barrels will yield a higher velocity while shorter or wider barrels will be yield a lower velocity.

As with all of PolarStar's electro-pneumatic conversion kits, you can quickly change and adjust key functions of JACK via the on-board FCU (Fire Control Unit) which is no bigger than an AEG's MOSFET and can easily fit inside of a rifles battery compartment along with a small Li-po battery. Using the FCU's five position joystick and LCD display you will be able to easily and precisely adjust such functions as the systems cyclic rate, fire modes and poppet dwell on the fly.

Although efficiency was not a critical requirement during development, JACK does boast some highly respectable figures in this category. This is made possible by is compact and intelligently laid out design which minimizes dead volume resulting in better air flow, faster response and less air used per shot. As a result JACK is considerably more air efficient than a bone stock Fusion Engine when operating in the same velocity range.

HPA system not included

Features:

  • Designed, manufactured and built in the U.S.A.
  • Assembled from CNC machined aluminum components with high performance delrin nozzle
  • Universal cylinder design is compatible with numerous gearbox versions
  • Optimized flow profile, firing point and flow path promotes superior shot consistency and accuracy
  • Capable of functioning in damp and sub-freezing climates without affecting performance or reliability
  • User selectable Semi/Full Auto, Semi Auto Only and Variable Burst modes
  • Independently adjustable velocity and cyclic rate
  • Auto Switch mode allows for proper selector configuration for specific models
  • Easy to use Fire Control Unit (FCU) with LCD display and five position joystick
  • Instantaneous trigger response. Faster than an AEG with a Li-po
Material: Aluminum / Delrin
Compatibility: A&K, Echo1, Classic Army, and Other Compatible M249 Series Machine Guns
Included Nozzle Type: M249 Series
Rate of Fire: 1 - 30+ RPS (Adjustable)
Muzzle Velocity: 500 FPS w/ .20g 6mm BB @ 120 PSI
Fire Modes: Semi / 2 - 9 Round Burst, Semi / Full Auto, Semi Only
Power Source: HPA (High Pressure Air via Remote Air Rig)
FCU Battery: 7-10VDC w/ JST Connector
PSI Operating Range: 40 PSI - 130 PSI (Do NOT exceed 130 PSI, otherwise you may damage the internals)
Package Includes: Pre-Assembled JACK Conversion Kit
Battery: 7.4v-9.6v NiMH or Lipo (Not included).

Manufacturer: PolarStar Airsoft

Required for Operation:Complete TM Spec AEG rifle with gearbox, Regulated Air Rig, HPA Tank, Battery (Sold Separately)

Installation: JACK will be installed into the shell of your AEG's gearbox. The only parts which you need to retain from your gearbox is the trigger w/ spring, safety assembly and selector components. Retain the original spring guide for models which require that the stock be secured to the gearbox and not the receiver.

Disclaimer on High Pressure Air (HPA) Systems:Only HPA or Nitrogen should be used with the JACK system. CO2 and Propane cannot be used. Using liquid propellants such as this can result in damage to the system.

HPA Tanks are a safe and effective source of power though there are some precautions you must follow. Please follow these proper precautions when using HPA systems:

- NEVER put oil in the fill valve of the tank, or else the tank can combust on refill and serious injury can occur. Lubrication is not necessary in HPA systems.
- ONLY allow properly trained professionals to fill your HPA tank.
- ALWAYS double check your Regulator pressure. Never raise the regulated pressure above 120 PSI
- Make sure to have your tank Hydro-Tested when necessary. (Usually 3-5 years from date marked on tank, depending on make and model)
- Be sure to properly transport your HPA tank. Store in a safe, secured place when in a vehicle, and be sure to stow in a bag or tank cover when in use. Avoid dropping the tank on hard surfaces as this can seriously damage the tank and lead to failure.
- Always turn off the tank and bleed the air line when you are done. This will ensure a longer tank and system lifespan.

About PolarStar

PolarStar Precision Airsoft was formed in January 2009 to fill a need for high quality, precision manufactured airsoft components designed for performance and longevity.The 2011 release of the patented Fusion Engine HPA system marked a change in direction for PolarStar. The focus shifted from developing upgrade components within the constraints of existing systems to developing innovative HPA systems and accessories which replace the aging AEG technology.PolarStar Airsoft is a division of PolarStar Engineering & Machine (PSE&M), a unique blend of tenured American toolmakers and a full service CAE/CAD/CAM (Computer Aided Engineering, Design, and Manufacturing), special crafts machine shop keeping alive our proud manufacturing heritage of Made in the USA. Founded in 1997, PSE&M began by servicing the automotive racing industry through the design and producing systems and components from art to part. Operating under the auspices of the Delaware Association of Professional Engineers, we retain a Professional Engineer (P.E.) on staff to ensure and certify all design and engineering standards are met. In addition to our own product line, PolarStar also offers engineering and manufacturing services tailored to the airsoft industry.

9 Customer Reviews

(Write a review)

by Noah B. on 07/28/2023
"Used in over 10 sessions at my indoor field. Not problems whatsoever. Great budget HPA engine.

Pros:
Trigger response
Reliability
Quietness
Ease of use
Programmability
Quality
Made in America
Changeable fps

Cons:
Price (This goes for basically every good HPA engine)
Does not come with 1/8 Male QD (Would recommend getting Amped IGL)

Conclusion:
Amazing HPA engine. Will last for a long time and if something does break, parts are readily available. If you don't want to constantly tech with aegs and want insane trigger response and adjustable fps, look no further.
by Alan A. on 12/07/2020
"Had this for almost a year and a half, and no real complaints.

PROS:
Shoots like a p*
Easily shoots over 60 rps without changing fcu settings other than ROF
Can be used at any field by adjusting psi input
Pisses people off just by looks
Easy to understand FCU
Burst, if you're into that
Can be used in any gun (Threw mine into a plastic $100 lancer tactical and it worked while I slowly upgraded it)
Useable by any battery
Battery can stay plugged in for a month and never die

CONS:
Full auto switch on trigger board doesn't get activated by the selector plate (most likely my cheap gearbox)
Often times will need to have foil tape added to make it secure in the gearbox

Love shredding through mags, it works like a dream, and with the right barrel assembly can laser people from across the field. It allows any type of build, from a small PDW SBR to a DMR that shoots farther than any other gun on the field. It can also be put in most other guns simply by changing the nozzle. Overall it's really great, obviously it's pricey but it shoots well and needs barely any maintenance. Don't forget the cost of the tank and lines though as that will set you back a good bit more, but if you can afford it, it will be incredibly fun to use.
by Tej M. on 05/05/2018
"Getting shots out to about 200ft, and hasn't broken yet, 10/10 IGN.

My Setup: Krytac MK1 CRB, ProWin Hopup, Flathopped Krytac Bucking, Modify Flathop Bucking.

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