The XD traces its roots back to a service rod known as the PHP (Prvi Hrvatski Pistolj or "First Croatian Pistol"), which was first produced in Croatia by privately owned industrial parts firm I.M. Metal in 1991. Designed by http://www.gunslot.com/guns/springfield-armory-xd a team led by Marko Vuković, the PHP was considered to be a solid design, but brand-new versions were plagued by quality issues, due in large bit to the difficulties of manufacturing during a liberation war. Vuković's team continued to tweak and improve the design over the abutting decade, releasing the HS95 (Hrvatski Samokres or "Croatian Pistol") in 1995, and the HS2000 in 1999 .

A fully supported chamber reduces the possibility of an bullet case rupture that could account injury to the shooter and severely deprivation the gun. This is an especially important component for owners who intend to use +P and/or reloaded ammunition.