The recoil spring assembly manages the energy cycle of the action—absorbing recoil as the slide or bolt moves rearward and returning it to battery for the next shot. The right spring weight is essential for reliable function, felt recoil, and component longevity.
AK Recoil Spring Assembly
AK-pattern rifles use a recoil spring and guide rod assembly that captures the spring between the dust cover and the rear of the bolt carrier. The standard assembly is simple and robust, but aftermarket options offer improvements in consistency and durability.
Standard/Mil-Spec: Mil-spec AK recoil assemblies are highly reliable and widely available. Proper spring tension is calibrated for standard 7.62x39 or 5.45x39 gas systems.
Enhanced/Heavy: For use with suppressors or overgassed AK variants. A heavier spring slows the bolt carrier and reduces the cyclic rate, which can improve reliability with suppressed setups.
Two-Stage/Progressive: Some aftermarket AK springs use a progressive rate design, starting lighter and stiffening as compression increases. This can reduce felt recoil while maintaining reliable cycling.
Glock-Compatible Recoil Spring Assembly
Glock-compatible pistol builds rely on the captured recoil spring assembly (RSA) between the slide and the barrel. The RSA is a wear item and should be replaced per manufacturer recommendations.
OEM Weight: Match the spring weight to your barrel length and caliber. Standard Glock assemblies are calibrated per model (G17, G19, G26, G34, etc.).
Captured vs. Flat Wire: Glock uses a dual-captured design. Aftermarket options include flat wire assemblies (Wolff, ISMI, Agency Arms) that offer smoother compression and longer service life.
Weight Options: Heavier springs reduce felt recoil but require more slide force to rack. Lighter springs improve rack-ability but may cause reliability issues with lighter loads.
Selection Guidelines
For AK builds, a mil-spec assembly is the correct starting point—switch to a heavier spring only if you are running a suppressor or experiencing short-stroking. For Glock-compatible pistol builds, match the RSA weight to your intended ammunition and barrel length. If you are running a compensator, a heavier spring is typically recommended to prevent over-cycling.