HB Industries Stribog Reduced Weight Trigger Spring Kit

The HB Industries Stribog Reduced Weight Trigger Spring Kit is the first trigger upgrade nearly every Stribog owner should buy. The kit ships two springs, an application-specific hammer spring and a matching disconnector spring, that work as a designed pair against the factory hammer, sear, trigger return spring, and trigger housing. Pull weight drops from a factory range of 6.0-6.5 lb to 4.5-5.0 lb, roughly a 25 percent reduction, with no change to hammer geometry or break character.

HBI tested reduced-weight trigger return springs during development and intentionally left the factory return spring in the kit. Their finding was that the OEM return spring produced a quicker and more positive reset than aftermarket lighter return springs. The kit ships only the two springs that actually need replacing.

Compatibility is restricted to 9mm Stribog variants. The SP9A1, SP9A2, and SP9A3 all share the same trigger module geometry and accept the kit. The SP10A3 (10mm) and SP45A3 (45 ACP) variants use different springs and are explicitly excluded. Install is a 10-15 minute bench job with a drift pin and basic gunsmith screwdrivers; HBI provides a video walkthrough on their site. Made in USA.