BoreBuddy AR22 Recoil Spring Kit: Custom Weights for Reliability The BoreBuddy Recoil springs are available in the following weights: 3lb (Light – BLUE) 4lb (Medium – YELLOW) 6lb (Heavy – RED) Stock springs vary in strength, but generally are between 4 and 5lb in recent production bolts. These recoil springs are designed to fit BoreBuddy/CMMG/RTB/PSA style dedicated bolts and conversion kits. 6lb spring recommended for most builds.
