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New Evike Outpost Locations! SAVE 20% with coupon code: EVIKEOUTPOST (Exclude MAP and SALE Items) Irregular Pitch Airsoft AEG Tune-up Spring (Model: M140 450~550 FPS)

ID: 53349 (SPR-EV-M140)
4.7 stars, based on 9 reviews Irregular Pitch Airsoft AEG Tune-up Spring (Model: M140 450~550 FPS)
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The AEG upgrade spring is the end result of research into some of the best selling springs on the market. Constructed of high grade stainless steel and formed with an irregular pitch, the upgrade springs roll all of the desirable features found in the most popular springs into one easy to install upgrade spring, with greater reliability and performance than most in the same price bracket.


  • Irregular pitch spring coils: Variable tension. Reduces stress, wear and tear for your gearbox
  • Strength: Made out of stainless steel. Increased tension and durability. Tension lasts 50% longer than other leading brands
  • Compatibility: Designed for all versions of Airsoft AEG gearboxes

Spring Power Chart. (% / FPS)

FPS estimate based on average power output. Exact FPS result may vary based on alignment, installation, inner barrel, cylinder and other factors.
  • 120% (M90) ~280~340 F.P.S.
  • 130% (M95) ~290~370 F.P.S.
  • 140% (M100) ~320~380 F.P.S.
  • 150% (M110) ~330~390 F.P.S.
  • 160% (M113) ~340~400F.P.S.
  • 170% (M115) ~350~420 F.P.S.
  • 190% (M120) ~360~450 F.P.S.
  • 210% (M125) ~400~470 F.P.S.
  • 235% (M130) ~420~500 F.P.S.
  • 260% (M140) ~450~550 F.P.S.
  • 300% (M150) ~480~600 F.P.S.
  • M160 : ~530+ 20 F.P.S.
  • M170 : ~560+ 20 F.P.S.
  • M180 : ~595+ 20 F.P.S.
  • M190 : ~625 + 20 F.P.S. Airsoft AEG Tip:

Always reset your spring by firing one shot in semi-automatic before putting it away.
M120 / 190% or stronger spring upgrade may require reinforcement of other gear box internal parts.
9.6V or Stronger battery may be required to power higher than stock springs.

For more info on your Airsoft AEG gearbox please refer to our video guides. AEG Gearbox Guides

California residents click here for Proposition 65 warning

9 Customer Reviews

(Write a review)

by curtis p. on 01/28/2018
"Mission accomplished. Installed in First gen Elite Force CQC with Torque motor and Reaps bucking. Chrono at field 350-352fps with .25's... Field limit Yeah!
by Alex H. on 01/22/2018
"Ordered two. M125 and M120. Good quality spring. Installed both into krytac mk2 spr with a 6.03 barrel. 125 shot 455fps with .20g. 120 shot 445fps with .20g. This was even after 1000 rounds to “break them in”. SHS m110 spring shoots 375fps with .20g. So I believe these springs are much stiffer.
by Ben S. on 09/03/2017
"Awesome spring!

Works perfectly as advertised. Nice construction. Super consistent. Installed the M125 into my Krytac MK2 CRB and now it shoots 405 FPS. Out of the box it shot around 415 FPS but settled down to 400-405 FPS. Perfect for my outdoor needs. Can't beat it for the quality and the price.

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