AEG Spring 120 [UNICORN]

This spring is way too strong. This isn t a M120 because M120 should normaly deliver around 1.40J. The readings I am having were way above at 1.90J (with a replica that has an average compression and "normal" chrono readings with other springs).

I installed this spring in my SRC G36 build and have been very satisfied with the results. The spring provides consistent 1,5 Joule and good performance without putting excessive stress on the gearbox. Build quality seems solid, and installation was straightforward. Overall, it's a reliable upgrade for anyone looking for stable power and durability.

The Unicorn AEG M120 Spring is a deceptively powerful upgrade that redefines expectations within its price range. At first glance, it may seem like just another standard spring—but once installed, it quickly becomes clear that this is a performance-focused component designed for serious airsoft players.
Crafted from high-quality German piano wire, the spring delivers exceptional durability and resilience under stress. This material choice ensures minimal deformation over time, even in demanding builds, making it a reliable long-term investment for upgraded AEG setups.

What truly sets the Unicorn M120 apart is its non-linear (irregular pitch) design. This advanced construction improves energy efficiency by pre-compressing certain sections of the spring, resulting in faster trigger response and a slightly increased rate of fire compared to traditional linear springs. The result is a snappier, more responsive shooting experience—especially noticeable in semi-auto engagements.

Performance-wise, this spring punches above its weight. While rated as an M120, many users report that it performs closer to higher-rated springs, often delivering stronger output than expected. In optimized builds, it can achieve around 390–420 FPS, depending on compression and internal components. This makes it ideal for outdoor fields or DMR-style setups where higher power is required.

However, that extra power comes with a caveat. The spring tends to be slightly longer and stronger than typical M120 equivalents, which means careful compatibility checks are essential. In certain configurations—especially with full-stroke pistons or bearing setups—it may require fine-tuning to avoid excessive stress on the gearbox.

Despite this, installation remains relatively straightforward for anyone familiar with AEG internals, and the payoff in performance is well worth the effort.
Final verdict:
The Unicorn M120 Spring is a hidden powerhouse—offering enhanced responsiveness, impressive durability, and above-average output for its class. It’s not just an upgrade; it’s a performance boost that rewards players who demand more from their builds.
Rating: 9.2 / 10
A high-performance spring that exceeds expectations—but demands respect in setup.

Ottimo prodotto, ottimo rapporto qualità prezzo conveniente, e resistente, lo utilizzo per una minimi e al momento va benissimo, ben fatto.
Consiglio
Ottimo sito, tempi di consegna rapidi e buoni prezzi

This spring is longer then others when compressed; so be carefull that you don't jamm-up your gearbox. Also, it's stronger then the rest of M120 from other manufacturers. This one is more like M140 or even M150. So , be carefull, if you have a full stroak piston inside and if you have a bearing on the spring guide and a bearing inside the piston - there is a good chance, that the spring will be too long

A very strong spring. It's a bit longer then other M120 springs and it's a lot more powerfull. It's about as strong as the SHS M140. Example of a setup: ZCI 455 mm barrel, ML mr.hop rubber, sealed nozzle, full cilinder and standard gears. It shot 0,32 bbs with around 2J (with some hop applyed).