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ACM M120 AEG Spring (SP120)
Boost your airsoft rifle's power, range, and velocity with the ACM M120 AEG Spring (SP120)! Engineered from high-tensile, heat-treated steel, this main power spring is designed to deliver consistent velocity in the range of ~380 to 420 FPS (depending on barrel length and compression setup). Featuring a stress-reducing non-linear pitch design, it compresses smoothly to minimize strain on your motor, gears, and piston head while maximizing shot consistency. Compatible with standard Version 2, Version 3, and most common AEG gearbox configurations, the ACM M120 spring is a reliable, budget-friendly power upgrade for outdoor field rifles!
£6.99
SKU
614474
Free Delivery & Returns*
SHIPPING OPTIONS
DELIVER TO
United Kingdom
United Kingdom
| TYPE | HOW MUCH? |
|---|---|
| Standard | £0.00 |
| Expedited | £4.99 |
DELIVER TO
Other countries
| TYPE | HOW MUCH? |
|---|---|
| International | £14.99 |
Reach further downrange and increase your muzzle velocity with the high-performance ACM M120 AEG Spring (SP120)! Designed as a direct drop-in main power upgrade for standard Airsoft Electric Guns (AEGs), this replacement spring delivers the added energy needed for long-range outdoor engagements, woodland skirmishes, and designated marksman build profiles.
High-Tensile Steel Construction & Non-Linear Pitch Crafted from high-strength, heat-treated steel alloy, the ACM M120 spring is built to resist tension fatigue and spring set deformation over thousands of firing cycles. It features an advanced non-linear (variable pitch) coil winding design. By spacing the coils unevenly along the length of the spring, the initial compression stroke requires less torque from your motor and bevel gear, reducing battery draw and mechanical shock at the start of the piston cycle. As the stroke completes, the tighter coil section releases maximum kinetic energy to drive the piston forward, producing stable, repeatable velocity shot after shot.
Targeted Velocity & Field Performance In a standard AEG build with optimal air-seal compression (using 0.20g 6mm BBs), an M120 rating typically yields between 380 and 420 FPS. This velocity bump expands your effective engagement range, helping your BBs cut through light wind and foliage at distance. Both ends of the spring are ground flat to sit flush against your spring guide and piston head bearings, preventing spring twisting, binding, or axial load distortion during rapid full-auto cycles.
Universal Gearbox Compatibility The ACM M120 spring is manufactured to standard AEG dimensions, making it universally compatible with Version 2 (M4/MP5/G3), Version 3 (AK/G36), Version 6 (P90), and most quick-change spring gearbox shells. Whether you are replacing a worn factory spring during a gearbox tune-up or building a dedicated outdoor field rifle from the ground up, the ACM M120 AEG Spring (SP120) provides reliable power, exceptional value, and long-lasting durability for your airsoft build.
| SKU | 614474 |
|---|---|
| Brand | Double Bell |
| Weapon Category | Parts |
| FPS | 301 - 400 |
| Spring Type | AEG |
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Delivery
Our courier partners deliver from Monday to Friday, excluding Bank Holidays. We will attempt to dispatch all packages within 24 hours, although at peak times this may take slightly longer. Orders with products with two-tone service or Defence Check may take longer to dispatch.
Once the order is dispatched you will get an email with the tracking number and which courier partner it’s going to be delivered via. Any missing/incorrect items need to be reported with 48hrs of signed delivery.
Returns
Click Here to Download the Returns Form (PDF Format)
Faulty Product?! Unfortunately that is part of life but be rest assured we are here to help! Contact one of our friendly staff via phone or email. Stating what the problem is, if we can resolve the problem via phone or email great if not then they will advise how to send it back and what details we require.
Two tone
We can two tone any weapon we sell at Bespoke Airsoft. The purpose for two toning is if you do not hold a valid defense under the Violent Crimes Reduction Act (VCRA, 2006) which is to prevent the misuse of Replica Weapons, which applies in England, Scotland, Wales and Northern Ireland.
The gun will be sprayed 51% in a bright/primary color (we do only blue, green and red currently). The process of two toning currently runs at 2 working days depending on Drying Time, which is effected by Ambient Temperature and Weather. and currently no express delivery is available for this even if you select it at checkout.
The gun will be sprayed 51% in a bright/primary color (we do only blue, green and red currently). The process of two toning currently runs at 2 working days depending on Drying Time, which is effected by Ambient Temperature and Weather. and currently no express delivery is available for this even if you select it at checkout.
FAQs
1. What is a BB gun used for? BB guns are mostly used for practice shooting and training. The stronger ones (i.e. Air Rifles) can also control pests or hunt small animals.
2. Do you need a Licence in the UK for a BB gun? No, you don't need a licence for a BB gun in the UK, but there are rules. The BB Gun needs to be in two colours; one has to be a primary. All our guns are on the website as per default.
3. Is a BB gun a good weapon? BB guns, despite sometimes being seen as toys, can be dangerous. They fire pellets at high speeds and can cause serious harm, or even be deadly in some situations.
4. Can you shoot BB guns in public in the UK without a Firearm license? BB guns in the UK navigate a legal grey area. While certain models, notably low-power 'soft air' types, typically evade classification as section 1 firearms, more potent versions may require a valid firearms certificate to avoid legal repercussions.
5. Can you shoot a BB gun in your garden? You can use a BB gun in your garden under UK law, but you have to ensure the pellets don't go into your neighbour's yard, plot or land. If they do and you don't have permission, it's against the law.
6. Which UK law am I breaking if the pellets go into my neighbour's law without permission? If your BB gun pellets go into your neighbour's yard without permission, you're breaking UK laws. Specifically, the 1968 Firearms Act and possibly the 2003 Anti-Social Behaviour Act, because you may be causing your neighbours trouble or worry.
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