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ASG Armalite M15 S.I.R. System Sportline Airsoft Gun

  • Armalite M15 S.I.R. System Sportline Airsoft Gun




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$9.99 for orders under $125


Fox Airsoft offers a 30 day warranty and return policy.


About the Armalite M15 S.I.R. System Sportline Airsoft Gun:

The M15 S.I.R. System is an M4 variant that features a custom rail.  The is packed full of features in a sportline M4.  The gun features a traditional crane style 6 position adjustable stock and standard pistol grip.  The highlight of the gun is the custom rail system that is licensed by A.R.M.S.  This was one of the first custom rails that came to the market for M4s.  The rail is mounted to the top receiver on the M4 and extends to the gas block.  Giving you a long top rail to mount optics on.  The system also features the 40L rear sight.  This sight is patented by A.R.M.S. and was one of the first folding back up iron sights developed.  If you have a red dot scope mounted to your rifle and it runs out of batteries, quickly deploy the 40L rear sight, and you are back in business.  The rail system on the sportline version is made out of a composite material to minimize weight.  The rail features multiple points that have mil standard 1913 picatinny rails for attaching accessories.  Included with the gun is a vertical foregrip.  The gun includes a 300 round M4 magazine to give you all of the firepower you need.  Just fill it up with some high quality 6mm airsoft BBs and you're good to go.  The gun does require a battery and charger as these are not included with the gun.  We highly recommend a Tenergy Butterfly Battery and a Tenergy Smart Charger - we've found this to be the best combination for most airsoft guns.  You can select these optional accessories when you check out to give you everything you need. This updated version of the gun has moved the battery to the rear, allowing for much easier installations.

What's Included in the Box: 

  • Armalite M15 SIR System Sportline Airsoft Gun
  • 1 x 300 Rd. Magazine
  • 1 x Vertical Grip
  • Manual
  • Cleaning Rod
  • 9.6v Battery and Standard Wall Charger are included

Quick Overview 

  • Composite Body
  • Composite Rail System
  • Adjustable Stock
  • 40L Rear Sight
  • 300 Rd. Magazine
  • Shoots 350 - 360 FPS out of the box

Technical Specifications 

  • Model Number: 50087
  • Muzzle Velocity: 350 - 360 FPS with .20 gram BBs
  • Color: Black 
  • Bearings/Bushings:
  • Spring Guide:
  • Piston: 
  • Gears:
  • Motor Type: Long
  • Piston Head:
  • Cylinder Head:
  • Cylinder:
  • Nozzle:
  • Spring:
  • Barrel:
  • Barrel Length: 363mm
  • Hop Up: 
  • Fuse: Yes
  • Battery Connector is a mini type Tamiya connector
  • Sights: Adjustable
  • Compatible Sling Types: 2 Point and 1 Point

Weight & Dimensions 

  • Dry weight of the gun without magazine or battery is: 5 lbs 4 oz
  • Weight of the gun with battery and without magazine is: 5 lbs 12 oz
  • Weight of the gun with battery and with magazine is: 5 lbs 7 oz
  • Entire Package Weight is: 7 lbs 0 oz
  • Gun Length Stock Collapsed: 30.5 Inches (775 mm)
  • Gun Length Stock Extended: 33.8 Inches (858 mm)
  • Package Dimensions: 33 x 10 x 4
  • Recommended Gun Bag Size: 36 inches
  • Recommended Maximum Battery Voltage: 11.1 volts

Images from the Manual:





Fox Airsoft offers a 30 day warranty and return policy which you can read more about here.  

Alternate Lookup: 50087

Warranty Information

9 Month Manufacturer's Warranty