A long trigger pull was designed into those guns. As the trigger is pressed to the rear, the top of the trigger pivots forward on pivot pin of the trigger bar. This causes the trigger bar to move forward and the trigger bar tail engages the hammer, causing the hammer to rotate back. Continual pressing of the trigger results in the trigger bar disengaging from the hammer which, now released from the restraint of the trigger bar, is propelled forward under pressure from the hammer spring (via the hammer strut). Can't do much about it other than snip off coils of the spring or buy a lighter spring. Mind you, when you do this, the reliability of the gun becomes questionable and you may not have the sure fire "bang" that you counted on in the past. Don't do it if this is a defense/CCW pistol.