KPYK SA-PJ13 Prime™ Aster ETU BLDC™ - Black

The Specna Arms x KPYK SA-PJ13 PRIME™ Aster ETU BLDC™ is an electric airsoft carbine (AEG) made for players who want a modern, compact and durable AK-platform rifle that already feels like a tuned build straight from the factory.

Developed in cooperation with KPYK, a Ukrainian company specialising in modern accessories for real firearms (especially AK platforms), this replica combines a solid steel construction, tactical KPYK externals and high-quality internals including a GATE ASTER V3 processor unit.

Construction and Materials – Steel Core with KPYK Handguard

The SA-PJ13 PRIME™ is largely made of steel, which gives it a solid and realistic feel:

• Steel parts include the dust cover, outer barrel, key barrel components, trigger guard, magazine catch, selector lever, sling loop on the stock, gas tube and the folding stock assembly.

Aluminium is used where strength and reduced weight both matter:

• Iron sights

• Muzzle device

• Side dovetail rail

• Charging handle assembly

• Handguard with CRC 1U020 gas tube cover from KPYK

Polymer components:

• Pistol grip

• Mid-cap magazine

The receiver features a Nano Coating finish, which helps protect it from minor scratches and wear.

With a weight of around 3590 g, the rifle keeps a realistic “all-metal” feel while still being manageable for full-day games.

Modern External Setup with Folding Stock

The SA-PJ13 is a tactical AK-style rifle designed for modern accessories:

• M-LOK handguard – easy mounting of flashlights, vertical grips, PEQ boxes and other accessories.

• Top Picatinny rail – ideal for red dot sights or compact optics.

• Side dovetail rail – for traditional AK optic mounts.

• 24 mm CW thread on the muzzle – ready for flash hiders or suppressors.

• Plenty of space for a stick-type battery under the dust cover.

A major advantage is the folding stock:

• When folded, overall length drops to about 730 mm, making it much easier to transport, store in a bag or vehicle, and move through tight spaces.

• When unfolded, you get a stable shoulder stock for accurate shooting at longer range.

This makes the SA-PJ13 a great choice as a universal outdoor assault rifle that can still be compact when needed.

PRIME™ Internals – Field-Ready Performance

The Prime™ Series combines the J-Series Edge 2.0™ platform with upgraded internals, so you do not need to start upgrading immediately after purchase. Inside the SA-PJ13 PRIME™ you will find:

• 6.02 mm precision inner barrel for improved accuracy and consistency.

• Specna Arms Magnus™ TDC rotary Hop-Up chamber – very fine, stable hop adjustment.

• Helium™ Flat Hop bucking – more stable BB lift, suitable even for heavier BBs.

• Steel cylinder for durability.

• CNC steel gears with 16:1 ratio – fast cycling and crisp trigger response.

• Reinforced piston with steel rack – built to handle higher stress.

• Aluminium cylinder head and aluminium nozzle – good air seal and steady FPS.

• 8 mm J-Cage ball bearings (motor and bevel gear) and an 8 mm slide bearing (spur gear).

With a muzzle velocity of about 430 FPS with 0.20 g BBs, this replica is primarily intended for outdoor gameplay, offering very good range and accuracy. As always, spring choice and power should match your local field limits.

Specna Arms DarkMatter™ High Speed 27–35K Brushless Motor

The drive system is powered by the Specna Arms DarkMatter™ High Speed 27–35K brushless motor:

• Brushless construction – no carbon brushes means less wear and longer lifespan.

• Fast trigger response – excellent for dynamic play and rapid semi-auto.

• Higher efficiency – better use of battery power and reduced heat build-up.

In practice, this means the rifle reacts immediately when you pull the trigger, runs smoothly and does not struggle even during longer bursts.

GATE ASTER V3 Processor Unit – The Brain of the Rifle

Electronics are controlled by the GATE ASTER V3 processor unit designed for V3 gearboxes. It is not just a basic MOSFET; it is a smart unit that protects the drivetrain and lets you tune how the rifle behaves.

Key features of the GATE ASTER V3:

• No USB-Link required for basic installation and configuration.

• New trigger detection algorithm and high trigger sensitivity out of the box.

• Multi-layer PCB for improved protection and better resistance to interference.

• Automatic pre-cocking for faster first-shot response.

• Full compatibility with brushless motors.

• Unlimited trigger sensitivity adjustment – set up a short, “sporty” trigger pull.

• Improved cycle detection.

• Multiple active brake modes: Adaptive / 100% / 60% / Brushless Motor / OFF.

• Reverse polarity protection.

• Trigger programming – set key functions via the trigger.

• Using USB-Link or Blu-Link, you can configure advanced functions, update firmware, run diagnostics and use the GCS app.

• Very low power consumption – only about 0.29 mA in deep sleep mode.

• Option to use a mechanical trigger lock.

Selectable firing modes (depending on configuration):

• Semi-auto – single shots

• Full-auto – standard burst fire

• Configurable burst – short burst with a defined number of shots

For the player, this means the rifle is better protected, highly responsive and easily customisable without having to open the gearbox every time.

ESA2™ Quick Spring Change

The SA-PJ13 PRIME™ is equipped with the ESA2™ Quick Spring Change system:

• Simply fold the stock and remove the rear cover to access the spring guide.

• No need to remove the entire gearbox from the receiver.

In the box you get two additional springs:

• M90 – for lower power, suitable for stricter field limits.

• M135 – for higher power where local rules allow it.

This lets you adapt the rifle to different fields and roles by changing the spring in a short time.

What’s Included

• Specna Arms x KPYK SA-PJ13 PRIME™ Aster ETU BLDC™ airsoft carbine

• 2× S-MAG mid-cap magazines (approx. 175 BBs)

• M90 spring

• M135 spring

• BB speedloader

• Cleaning rod

• Small Tamiya to DEANS (T-connect) adapter

Battery and charger are not included.
We recommend a good quality LiPo or Li-Ion battery with a DEANS / T-connect plug.

Who Is This Rifle For?

The SA-PJ13 PRIME™ is an excellent choice if you:

• Want a modern AK with a folding stock, suitable for vehicles, buildings and outdoor fields.

• Are looking for a high-performance outdoor rifle with good range and accuracy, without needing immediate internal upgrades.

• Appreciate fast trigger response and smooth operation thanks to a brushless motor.

• Want a GATE ASTER V3 processor unit with the option to fine-tune behaviour via GCS and USB-Link / Blu-Link.

• Prefer one universal rifle whose power you can adapt just by changing the spring.

Key Reasons to Choose the SA-PJ13 PRIME™

• Ready to play without extra tuning – precision barrel, quality hop-up, steel gears, reinforced piston, brushless motor and a GATE ASTER V3 processor unit straight from the factory. No need to invest in upgrades right away.

• Folding stock and compact size – significantly shorter when folded, ideal for vehicles, transport or events where you need a rifle that can quickly go from compact to combat-ready.

• Steel construction and modern KPYK handguard – realistic metal feel, high durability and modern M-LOK interface for accessories.

• Smart GATE ASTER V3 processor unit – protects both internals and battery, allows very fine trigger, braking and firing mode adjustments, and can be expanded via the GCS app.

• DarkMatter™ brushless motor – fast response, efficient power transfer and lower wear compared to standard brushed motors.

• ESA2™ quick spring change – easy power adjustment without a full gearbox teardown, so one replica can handle several field types and limits.

If you are looking for a compact, modern and durable AK-style rifle with strong performance straight out of the box, the Specna Arms x KPYK SA-PJ13 PRIME™ is a replica you should seriously consider.