Walther P5 - PT Barrel in 8,2mm-9T

Walther produced a barrel that was specifically made to shoot the 9x19mm plastic training ammo. The barrel can be installed in any P5 (not the compact) without further modifications, and the blue plastic trainings ammo can be loaded in standard P5 magazines. The barrel has a caliber of 8.2mm which is smaller than the caliber of the munition. It is believed that this is done to overcome cycling problems. Shooting the plastic training ammo in original barrels is subjected to cycle problems. The reason is that the blue bullets do not build up sufficient pressure to cycle a new round.  The smaller diameter of the PT barrel is believed to cramp the bullet more (which is possible with plastic bullets), allowing to have a better gas seal and higher friction, and therefore a more desireable pressure build-up to enable cycling of the weapon.

The barrel shown here was produced in 1993 (code KD). These training systems were shortly used by the Dutch police. A rare bird to find...