Description
MPN: SLA502S-K
Features:
- Complete Recoil Upgrade: Kit includes the VPRS-15 Variable-Pitch Recoil Spring + T-2 buffer—drop-in smoothness and control
- Less Felt Recoil: Progressive coil spacing “cushions” the BCG—breaks up initial impact and slows the carrier for smoother cycling
- Runs Across Calibers: Listed to work phenomenally in 9mm blowback and 300 BLK builds in addition to 5.56 setups
- Spring Tech: Marketed as the only AR variable-pitch recoil spring, developed with Cook Spring Co.
- Easy Choice, No Guesswork: “One spring for your AR platform”—no juggling different spring weights
- American Made + Lifetime Warranty: Backed by Spike’s Tactical
Specifications:
- Material: Steel
- Spring Weight: 1.9 oz.
- Buffer Weight: ~4 oz.
Compatibility:
- Carbine buffer tubes
- Pistol buffer tubes
Includes:
- 1x Spike's Tactical VPRS-15 Buffer Spring
- 1x Spike's Tactical T2 Tungsten Buffer
Details:
If your AR feels a little slap-happy through the buffer tube, the Flatline Kit is the fix. It pairs Spike’s VPRS-15 variable-pitch recoil spring with the T-2 buffer so the recoil system works as a matched unit—not a guess. The spring’s staggered coil spacing cushions the initial impact, then progressively slows the carrier as it moves rearward. On the gun, that spreads the impulse, takes the edge off felt recoil, and delivers a calmer return to battery—less slam, less sight bounce, cleaner follow-ups.
How It Smooths the Cycle
Unlike single-pitch springs, the VPRS-15 changes rate as it compresses. That progressive action helps prevent the carrier from hammering the back of the extension and reduces the “boing” you feel and hear through the stock. Paired with the T-2 buffer’s added mass, you get a controlled stroke that tracks flatter and feels more predictable at speed.
Tuned to Tame More Than 5.56
This isn’t a one-trick spring. The VPRS-15 is built for standard AR-15 carbine receiver extensions and shines in setups that can run hot—9mm blowback and .300 BLK are specifically called out by Spike’s. Instead of juggling different spring rates for different uppers, drop this kit in and get consistent, repeatable behavior across hosts. The T-2 adds just the right weight to keep things smooth without making the rifle feel nose-heavy.
Drop-In Simplicity, Duty-Ready Durability
Installation is as straightforward as any carbine spring and buffer swap: pull the buffer, replace the spring, install the T-2 buffer, and you’re back on the line. Made in the USA and backed by Spike’s, the components are built for high round counts and everyday use, so you’re improving reliability—not introducing variables.
Why It Belongs in Your AR
By treating spring rate and buffer mass as a system, the Flatline Kit makes an AR feel sorted—on a 5.56 carbine, a blowback PCC, or a .300 BLK range gun. Expect a smoother cycle, quicker sight recovery, and fewer hiccups when you start pushing the pace—all with the same manual of arms you already know.
