ISMI Recoil Spring for Smith & Wesson SD9 & SD40 VE 20lb

Bring race-grade performance and durability to your Smith & Wesson SD pistol. The ISMI 20 lb. recoil spring for the Smith & Wesson SD9 & SD40 models is a heavy-duty replacement spring engineered to control slide velocity with stout loads, suppressors, and high-stress duty use. Manufactured from certified aerospace alloys then heat-treated, shot-peened and stress-relieved; ISMI springs hold tight tolerances and deliver long, predictable service life compared with standard music-wire options. This recoil spring provides a 20 lb. spring rate to slow slide velocity, improve lock-up timing, and reduce frame stress when running heavy loads, +P ammunition, or suppressors. Stabilizes slide timing over thousands of rounds for more consistent feed, lockup, and trigger reset. Get yours at NDZ Performance today!

Features:

• 20 lb. spring rate: Tuned for heavy loads, suppressed or compensated builds, and high-round-count use.
• Aerospace-grade materials: Chrome-silicon or stainless alloys for superior fatigue resistance.
• Racing-level processing: Heat treated, shot-peened and stress-relieved for predictable compression behavior and extended life.
• Tighter tolerances: Better spring-rate repeatability and less relaxation over time versus music-wire springs.
• Direct-fit: Designed for SD9/ SD40 & VE platforms (confirm exact model before ordering).

Important: Not compatible with Glock Guide Rods, using these springs with a Glock guide rod in your SD9 or SD40 will result in damage to your firearm. 

See our complete line of Springfield SD9 & SD40 Products here

Note: NDZ always recommends any part be installed by a qualified and trained gunsmith. NDZ promotes the use of safety practices and gear when working on any firearm.