ASG M40A3 McMillan Sniper Rifle SportLine

  • Bolt Action
  • Fully Licensed Replica
  • Adjustable Cheek Rest

Fully licensed by McMillan, this bolt action 6mm BB Airsoft sniper rifle is a 1:1 scale replica of the US Marine Corps’ M40A3 sniper rifle, complete with accurate McMillan branding.

Full description


Part of ASG's SportLine Sl beginner's range, this is both a highly authentic Airsoft replica of the M40A3 rifle and an affordable bolt action Airsoft sniper rifle which boasts great perfomance out of the box. Based on a rugged military design which has seen service with the United States Marine Corps since 2001, the ASG M40A3 is a 1:1 scale spring powered bolt action Airsoft sniper rifle. 

Just like the real M40A3, this quality Airsoft replica from ASG features dual alloy and polymer construction. Accurate to the real design, the Airsoft M40A3 uses a lightweight and durable polymer Stock, which holds the alloy barrel, receiver and bolt. To top it all off, the replica features fully licenced and accurate markings and branding from McMillan, making this Airsoft replica almost indistinguishable from the real thing. 

A 20mm RIS rail located on the upper face of the receiver allows users to attach a wide range of sights and scopes as they wish. The lower face of the handguard features a short section of 20mm rail, providing ample space to install tactical accessories such as a bipod or foregrip. User comfort can be improved thanks to the stock’s adjustable cheek rest and buttstock. The cheek rest can be raised or lowered without tools, to ensure that users are able to get the best possible eye relief when aiming, whilst the stock’s length can be adjusted to ensure that users can comfortably hold and aim the rifle. 

The rifle features an adjustable Hop Unit, which makes a positive click when it is being adjusted, and allows for a wide range of BBs to be used, including heavy weight BBs designed specifically for use in sniper rifles. Straight out of the box the ASG M40A3 is an excellent performer on the Airsoft skirmish field, able to hold its own next to some of the more high end Airsoft sniper rifles. However, for those of you wanting to get the best possible performance, the M40A3 is completely upgradeable, and is fully compatible with ASG SSG aftermarket parts, such as replacing the barrel and spring to greatly enhance the gun’s range and accuracy. 

If you’re looking to get into sniping, either as a new Airsofter or veteran skirmisher, then the ASG M40A3 is a great place to start – for a sniper rifle in this price range, we think you’ll be pleasantly surprised by the performance. For anyone attempting to create a USMC marksman loadout from 2001-2015, then the ASG M40A3 is both an excellent and accurate choice.


  • Fully licensed by McMillan 
  • Based on the M40A3 sniper rifle used by USMC
  • Part of ASG's SportLine SL beginner range
  • Great performance for a great price
  • Top 7'' 20mm RIS / RAS rail for attaching sights and scopes
  • Lower 2.5'' 20mm RIS / RAS rail for bipods and accessories
  • Front and rear right side swivel sling mounts
  • Textured handguard and grip for enhanced grip
  • Adjustable cheek rest for perfect eye relief on your sight
  • Adjustable linear Hop-up unit for range and accuracy
  • Adjustable Stock length via removable plates
  • Hop-up clicks on adjustment
  • Removable barrel cap for replacing with a suppressor adaptor
  • Trigger lock safety switch
  • 1:1 scale Airsoft replica
  • 27rnd spring loaded magazine
  • Can be upgraded with aftermarket SSG parts
  • Unique serial number
  • Branded:
    • 'ASG'
    • 'F'
    • 'Cal. 6mm BB'

Package Includes:

  • M40A3 McMillan Sniper Rifle
  • Magazine 
  • Instruction Manual
  • Stock Extension Plate Set
  • Unjamming Rod
  • Speed Loader
  • Allen Key Pair



Weapon Construction External
Weapon Type
Snipers Rifle
Over 18 Only Icon
Over 18
Icon UKARA - United Kingdom Airsoft Retailer Association
Defence / UKARA Required
Yes, No,
FPS Icon
FPS (Feet Per Second), using 0.20g BB
Approx. 364fps ± 10%, using 0.20g BB
Site Legal Icon
Site Legal, using 0.20g BB
Included Items
  • Magazine
  • Instruction Manual
  • Cleaning Rod
  • Speed Loader
  • Allen Key
  • Stock Extension Plates
Skill Level Icon
User Skill Level

Weight and Dimension

Weight KG Icon
Weight (KG)
Approx. 2.316kg
Weapon Length Collapsed
Length (Collapsed)
Weapon Length Extended
Length (Extended)


Colour Wheel Greyscale
Primary Colour
Colour Wheel Greyscale
Secondary Colour
Two Tone Icon
Pre Two-Toned
Construction Icon
Polymer Stock with Alloy Outer Barrel, Bolt Housing, Pins, Screws and Internals
Weapon Construction External
External Construction
Gearbox Icon
Internal Construction

Weapon Specific

Power Source Icon
Powered By
Blowback Icon
Weapon Platform
Magazine Style Icon
Magazine Style
M40 Spring
Fire Select Icon
Fire Selector
PatrolBase | Fire Select Safe
Fire Select Icon
Variant Fire Selector
PatrolBase | Fire Select Safe
Shooter Configuration Icon
Shooter Configuration
Right Handed
Weapon Configuration Icon
Weapon Configuration
Bolt Action
Weapon Scale Icon
Weapon Scale
Suggested BB Weight


Hop-Up Unit Icon
Hop-Up Unit
Hop-Up Unit Adjuster Icon
Hop-Up Adjuster
Hop-Up Unit Location Icon
Hop-Up Location
Linear on the Left Side of the Barrel


Weapon Furniture Icon
  • Railed Receiver
  • Adjustable Cheek Rest
  • Harris Bipod Lug
Rail System Icon
Rail System
20mm RIS / RAS
Sight Type Icon
Sight Type
Sling Plate Icon
Sling Options

Magazine Specific

Magazine Type
Low Capacity , Spring Loaded, Sniper Rifle,
Magazine BB Capacity
Approx. 27 Rounds
Magazine BB Fill Method
Speed Loader
Magazine BB Fill Location

Product Testing Data

Notepad Icon
Test Description
Using 0.20g BB
Notepad Icon
Tested Using
ASG 0.20g Blaster 6mm BB x 3000
Notepad Icon
Test Date

Customer reviews

5 / 5
1 review for ASG M40A3 McMillan Sniper Rifle SportLine customer reviews
Didnt expect much of it out the box to be honest but performance is great money well spent
Rated 5 out of 5

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