AR-15/M16 Enhanced Flat Wire Recoil Spring - Gen 2

MSRP: $26.99
Our Price: $23.99
(You save $3.00 )
(9 reviews) Write a Review
Adding to cart… The item has been added

Good enough wasn't good enough, so I'm proud to introduce the Gen 2 AR-15/M16 Flat Wire Recoil Spring! Most notably, if you're familiar with the original FWS, the Gen 2 FWS now fits over all buffer styles with no binding.

Round wire springs have been the standard since the inception of the AR-15 in the 1950's. Compared to round wire springs made of music wire, stainless steel, or even chrome silicon, our Enhanced Flat Wire Spring does numerous things better than its round wire counterparts. Our Flat Wire Spring places more load on the bolt when it is in battery which causes dwell time to increase slightly which drops chamber pressures before extraction and reduces rearward BCG velocity. It also helps push the bolt back into battery through adverse conditions and fouling, helps to strip stubborn rounds out of magazines, and can even help reduce or eliminate bolt bounce. When the bolt is locked open, our Gen 2 Enhanced Flat Wire Spring places the same amount of force on the bolt as traditional round wire springs.

Spring Load in a Carbine Length Buffer Tube:

Bolt Forward in Battery:

Bexar FWS ~ 7.5 lbs
Mil-Spec     ~ 6 - 6.5 lbs

Bolt Locked to Rear:

Bexar FWS ~ 12 lbs
Mil-Spec     ~ 12 - 12.5 lbs

Bring your AR into the 21st century with a Bexar Arms Enhanced Flat Wire Recoil Spring!

The Gen 2 AR-15 Flat Wire Spring is designed and optimized for use in Carbine Length buffer tubes. If you're running an A5 or Rifle Length buffer system, please use our A5/Rifle Spring Spacer in conjunction with our Gen 2 FWS.

100% Made in the USA

A note from Phillip: If your spring still has some rattle or twang once installed, try using some of your favorite automotive grease on the buffer and spring. I personally prefer the full synthetic Lucas X-TRA Heavy Duty "green" type of grease. You'll know if you've used enough when you drop the bolt on an empty chamber and the twang is gone!


  • Gen 2 AR-15/M6 Enhanced Flat Wire Buffer Spring
  • Optimized for Carbine Length Buffer Tubes
  • 17-7 PH Stainless Steel Construction
  • Improved Spring Load Characteristics
  • Reduces/Eliminates Bolt Bounce
  • Reduces/Eliminates Spring Rattle
  • Lifetime Warranty
  • Weighs 2 oz
  • 100% Made in the USA

Recommended Uses:

Use our AR-15 Enhanced Flat Wire Buffer Spring on any gas operated small frame AR calibers such as:

  • .223 Rem/5.56 NATO
  • 6mm ARC
  • 22 Nosler
  • .224 Valkyrie
  • 300 Blackout
  • 6.5 Grendel
  • 6.8 SPC
  • 7.62x39
  • 9mm PCC straight blowbacks
  • etc.

DO NOT use with the following:

  • Receiver Extensions shorter than Carbine Length
  • AR-10/SR25 or any Large Frame AR's
  • .308 Win/7.62x51 NATO
  • 6.5 Creedmoor
  • .260 Remington
  • .243 Winchester
  • etc.
While buffer springs are normally a wear item that are replaced in regular service intervals, we are so confident that our Enhanced Flat Wire Springs will never be shot out or damaged from normal shooting that we guarantee it for life! Should you somehow manage to make our Enhanced Flat Wire Buffer Spring fail to do its job, contact us and we will send you a replacement free of charge. Should you try our Flat Wire Spring and decide it's not for you, please contact us for a full refund. We will refund you the cost of the spring, the original shipping charge, AND send you a free return label. Warranty does not apply to any springs that have been permanently modified in any way.

9 Reviews Hide Reviews Show Reviews

  • 5
    Gen 2 flat wire recoil spring is g2g

    Posted by Trent on Aug 16th 2021

    Spring is quiet, sproingy, and works. I thought it might be snake oil but it really is quieter and just feels nicer. Fits in the tube, and the gen 2 fits my heavy buffer. I think the gen one had issues with fitting heavy buffers, and I had one where I had to sand down my buffer to get it to fit. The gen 2 is plug and play with a new buffer identical to the one I had to sand before. I like it

  • 5
    Works real well.

    Posted by Robert Marsh on May 13th 2021

    Thank you Phillip. It works real well. And thank you for the sticker. My wife loved it and put it on her car

  • 5
    Works perfect

    Posted by Zach on May 3rd 2021

    Works perfect. Definitely an upgrade from a basic spring.

  • 5
    Buffer spring

    Posted by BkfitMP5 on Apr 7th 2021

    Placed in my MK18 with a H2 very good spring. Fast shipping. GTG, get one!

  • 5
    Pleasantly Surprised

    Posted by John on Apr 1st 2021

    I was pleasantly surprised by how much these improve performance with followup shots being easier as the recoil is smoothed out. There isn't less recoil, it's just smoother cycling so it is more manageable in its recoiling. I just bought another 2 so all my carbine lowers have these flat springs now. Only downside is installation is a little annoying as the springs get caught on the buffer detent and you need to press down the detent as you install the springs but it's worth the performance upgrade. I'm converted.

  • 5
    Just do it

    Posted by E$ on Mar 4th 2021

    If you’re on the fence about this, just do it. Easily one of the best modifications I’ve done to any of my rifles

  • 5
    First Upgrade You Should Make!

    Posted by Mika Howser on Feb 24th 2021

    This flat wire is awesome. I have both a captured spring and 2 of these flat springs. When shooting the two rifles suppressed both devices do an excellent job of getting rid of the “twang!”. The flat spring is a bargain for what it does. Every build I do going forward will have one of these. A must have in my books!

  • 5

    Posted by John on Jan 18th 2021

    I purchased 2 of these flat wire springs. One for my Springfield Saint and one for my 11.5” pistol build. These things are pretty sweet. No more twang. Installation was a little more difficult than the Mil-Spec ones I had. It’s because of the flat edge. No big deal though, I used a little grease and just screwed the spring into the buffer tube. I would highly recommend this spring. It has to be one of the cheaper and easier upgrades one can make to an AR. Service was quick and it even came with a hand written thank you note. They have definitely earned more of my business.

  • 5
    Great flat wire!

    Posted by Andrew W on Jan 4th 2021

    I'm very pleased with the performance of this new buffer spring! It fits my buffer perfectly and feels great to shoot. Plus, it shipped quickly and customer service has always been 10/10 with Bexar.