45 GAP Ammunition was Particularly designed for Glock and "GAP" actually means "Glock Computerized Pistol". Engineer Ernest Durham made the forty five GAP round like a cartridge that would be as potent as 45 ACP but would've a much better circumstance head to decrease the possibility that the case's neck https://tacticalrounds.com/product-tag/geissele-trigger-single-stage/