Specna Arms SA-C21 CORE™ HAL¹ ETU™ M4/AR-15 AEG

If you're looking for a fresh and modernised CQB platform, the Specna Arms SA-C21 CORE™ HAL¹ ETU™ M4/AR-15 AEG is one should consider. Constructed to Specna's CORE standard, the SA-C08 boasts a CNC aluminium handguard and alloy outer barrel and bird cage muzzle attachment paired with a high-density polymer receiver, buffer tube, stock and pistol grip, giving you a great introduction to more realistic replicas, but still easy to use during a day of skirmishing. As with the original CORE series, the polymer quality is top-notch, more scratch-resistant than comparable metal receivers and ultra-light for high energy throughout the skirmish day. 

Inside this, the latest SA-C21 variant, we are treated to the HAL ETU/MOSFET, a lovely addition to a beginner rifle! The HAL¹ ETU offers binary trigger, AUG mode and sniper delay instead of semi-auto and semi-auto lock, 3-round burst or 5-round burst instead of full auto, along with several quality-of-life improvements and most importantly for CQB, adjustable pre-cocking! Pre-cocking positions the piston at the rear of its cycle after a shot, meaning when you pull the trigger the response is practically instantaneous, ideal for semi-auto duels in the close confines of a CQB site.

A considerable improvement over the original SA-C21, the HAL¹ ETU adds a lot of functionality to this lightweight beginner-friendly platform. With no more trigger lock-ups when shooting semi-auto, plenty of fire mode options and the pre-installed 6.03mm tightbore inner barrel and rotary HOP-up combo which made the original SA-C21 CORE such a solid choice, the new version is hard to beat!

Starting at the front end of this stubby platform, we can find a birdcage flash hider pre-installed on the 14mm CCW male outer barrel threading. The birdcage is the classic M4/AR-15 flash hider design and looks fantastic, but if you are a more discrete skirmisher or you plan to run a tracer, you can swap it out for a 14mm CCW compatible muzzle device of your choice.

Moving rearwards, you will find the M-LOK handguard which is made from aluminium using CNC machining, guaranteeing that the attachment slots and rails are in flawless form. M-LOK handguards are known to give the replica a cutting-edge look with their sleek style and angular look. The M-LOK slots are present at the 3, 6 & 9 o'clock positions with a 20mm Picatinny rail up top equipped with the included flip-up aperture iron sights. The benefit of a modern M-LOK handguard is that in its slick configuration, the handguard is lightweight and surprisingly ergonomic, meaning you don't need to add rail covers to avoid the rough edges as you might with a 20mm quad rail. 

Also present on the M-LOK handguard, there are two QD sling points on either side. These QD points are perfect for those who like to be nimble on the battlefield. This platform is already so small that it is unlikely to get in your way when manoeuvring around the skirmish field, however, the addition of the QD sling points makes it even easier to carry this replica around the battlefield. 

Next up we reach the receiver, which is instantly recognizable as the common M4/AR-15 configuration, with its controls laid out in a considerate and ergonomic manner, allowing the SA-C21 to be manipulated quickly and instinctively by veterans, or learned rapidly by new users. The receiver is constructed from a lightweight but high-density polymer, which makes it lighter than alloy receivers but just as strong!

Pulling back the extended charging handle, at the rear of the receiver, will pop open the dust cover and retract the mock bolt carrier which allows access to the rotary HOP-up adjuster. This is the latest HOP-up unit design for the M4/AR-15 and provides finer increments of adjustment and holds its setting more effectively when compared to the older gear style HOP-up unit. The charging handle has an extended latch for easier access, allowing even those with thick gloves to access the HOP-up unit, though you may need to remove your glove to adjust the unit!

The bolt catch on the left side of the receiver does not function but is nonetheless a separate moveable part to reduce the common tell-tale signs of a replica. The forward assist is a similar story, being present on the right side of the upper receiver and being another separate moving part which can be pressed in but has no effect on the function of the AEG. A new addition to this HAL-equipped SA-C21 is its flat trigger, enhancing the military aesthetic with a touch of modernity and providing an easily slappable trigger for snappy double taps in semi-auto. 

The pistol grip of the SA-C21 is an M16A2/M4A1 style pistol grip, also known as the "A2" finger ridged grip. The A2 has diamond checkering on either side and linear texture on the back strap to provide excellent gripping qualities whether you wear gloves or not. The finger ridge is designed to help you keep hold of the rifle and prevent the grip from slipping out of your hands when held in a single hand. As with most M4/AR-15 AEGs, this grip is compatible with aftermarket M4/AR-15 AEG grips, ideal for customisation addicts!

The battery compartment is inside the crane stock, accessible by squeezing the two tabs at the toe of the stock together, after which you can lift the butt plate off, remove the battery plug and make use of the stock's built-in battery compartment to house a nunchuck/crane-style battery. Being equipped with the HAL ETU, we are also treated to a Deans/t-plug battery connector, a lower resistance alternative to the mini-Tamiya found on previous Specna Arms CORE AEGs. For the SA-C21, we recommend a 7.4V 1450mAh LiPo crane/nunchuck battery for an easy fit and great performance.

The Crane stock also includes a pair of QD sling sockets, one on each side, allowing for QD sling swivels to be added for a quick removable sling setup. Conventional sling slots (aka "footman loops") are also present for those who want a two-point sling but prefer the old-fashioned way. The butt plate is also made from grippy rubber, ensuring your SA-C21 doesn't slip off your shoulder at a critical moment. 

Inside the HAL¹ equipped SA-C21, we have an alloy V2 gearbox shell with 18:1 ratio steel gears running on 8mm bushings. The spring guide is an ESA quick change example, making power tuning a breeze for those who want to get as close to site limits as possible. The inner barrel is a 6.03mm tightbore paired with a rotary HOP-up unit, giving you superb accuracy potential and the most up-to-date HOP-up unit style for M4/AR-15 AEGs. All internal parts are Tokyo Marui AEG spec, meaning aftermarket upgrades are a go for the performance seekers!

The HAL¹ adds a whole lot of functionality into the mix, with programmable fire controls, 6 levels of pre-cocking adjustment and 5 levels of trigger sensitivity adjustment. Available fire modes include 3 or 5-round burst, binary trigger, AUG mode aka two-stage trigger, semi-auto only and sniper delay, giving you loads of options for how you use your SA-C21. Features like these are usually only present in high-end replicas; we simply cannot believe the wealth of functionality inside the HAL¹ equipped SA-C21, especially considering the price!

If you're in search of a new AEG for your close-quarters skirmishes, then the Specna Arms SA-C21 CORE™ HAL¹ ETU™ M4/AR-15 Carbine AEG is certainly one for you. With its advanced functionality and slick modern handguard interface, this AEG is incredible for any player and its low price point is certainly attractive to anyone! Whether you're a newcomer to Airsoft or you're a pro looking for a lightweight back up, the SA-C21 is a great choice for all!

Features

• 6.03mm Tightbore inner barrel - Great accuracy potential
• High-density polymer with CNC Aluminium handguard 
• Perfect for CQB skirmishing, compact and lightweight, provides great manoeuvrability!
• Birdcage Flash Hider pre-installed
• 14mm CCW Male threaded outer barrel
• M-LOK handguard - Super slick and streamlined
• Flip-up aperture iron sights pre-installed - Adjustable for windage and elevation, 2 apertures to choose from
• 20mm Picatinny railed receiver - Ready for red dot sights, PEQ lasers or scopes to be mounted
• Rotary adjustable HOP-up unit - The latest M4/AR-15 design, holds its setting well and allows for fine adjustment
• Finger ridged "A2" pistol grip - Comfortable for most hand sizes, textured for extra traction
• Flat mil-spec trigger guard - Matches real US Army-issued M4A1 rifles
• 3-Position fire selector switch - SAFE, SEMI AUTO & FULL AUTO, 90-degree throw between each mode
• Extended charging handle - Fast access to the HOP-up unit for quick mid-game adjustment
• 6-Position M4/AR-15 buffer tube - Adjust the stock quickly and easily to suit your body type or loadout
• Crane stock pre-installed - Plenty of battery space, QD sling sockets built-in
• Version 2 Gearbox:
  • 8mm bushings
  • ESA quick change spring system
  • Steel 18:1 ratio gearset
  • Alloy shell
• HAL¹ Programmable MOSFET/ETU functions:
  • Low voltage alarmActive braking 
  • Adjustable pre-cocking (6 levels)
  • Two-stage trigger (AUG mode)
  • Sniper delay
  • Semi-auto only
  • Binary Trigger
  • 3 or 5-round burst
• HAL¹ Programming instructions available here
• Compatible with M4/AR-15 AEG magazines - S-Mag High-cap | S-Mag Mid-cap | S-Mag Mid-cap 5 Pack
• Rear wired: Deans battery connector - Recommended battery: 7.4V 1450mAh LiPo in crane/nunchuck config

Package Includes

• Specna Arms SA-C25 CORE™ HAL¹ ETU™ M4/AR-15 AEG
• 300rnd S-Mag M4/AR-15 High-cap magazine
• Cleaning rod