Winchester 1964 SPIW: Flechettes and a Blow-Forward Grenade Launcher
The Winchester 1964 SPIW was a prototype developed for a 1962 U.S. military program seeking a multi-purpose combat rifle. It featured flechette ammunition for point targets and an integrated 40mm blow-forward grenade launcher. Despite innovative concepts like a soft recoil system, the SPIW suffered from poor balance and reliability issues, ultimately failing to be adopted.









