45 GAP Ammunition was Particularly designed for Glock and "Hole" basically means "Glock Automated Pistol". Engineer Ernest Durham created the 45 Hole round to be a cartridge that could be as highly effective as 45 ACP but would have a much better circumstance head to decrease the likelihood that the https://tacticalrounds.com/product-category/best-rifle-ammo/5-45x39mm-ammo/