The Canadian firm of Para-Ordnance has been a trailblazer when it comes to improving the classic 1911 pistol. One of the company's most radical concepts is the Light Double Action (LDA) trigger mechanism, which can be found on its new Carry 9 LDA.
Light Double Action
Unlike most other double-action-only pistols on today's market, retracting the slide of an LDA pistol rotates the hammer and a cam, which compresses the mainspring on the hammer strut. The hammer follows the slide as it goes forward until it is stopped by twin locking hooks, engaging the sear. This holds the hammer short of contacting the firing pin until the trigger is pulled through a complete stroke, cocking the hammer and moving the sear out of its engaged position, allowing the hammer to fall.
After firing, a return spring pushes the trigger forward as it is released, and the top end of the trigger moves rearward, moving a drawbar with it. As the drawbar moves rearward, it is released from underneath the firing pin safety plunger lever, and is then pushed upward by a unit called the platform and platform spring, where it reconnects with the hammer and is aligned in position to re-contact and release the sear the next time the trigger is pulled. When the trigger is pulled, it pulls the drawbar forward, cocking the hammer, which in turn contacts and disengages the sear, allowing the hammer to fall and strike the firing pin.
The hammer is not under tension from the mainspring until it is cocked and can pick up the cam. The result is a light, smooth trigger stroke with a single-action-type let off at the end.
LDA pistols have traditional 1911-type controls, including manual and grip safeties. It should be noted that the slide cannot be retracted unless the grip safety is fully depressed. The LDA has found ready acceptance with police officers who wish to carry a 1911 pistol but whose departments' policies do not allow single-action pistols.
Unlike many of my associates in the firearms media, I am an unabashed fan of Georg Luger's cartridge. It is my all-time favorite pistol round, and for good reason. The 9mm Para is accurate, produces light recoil, is inexpensive, and can be chambered in pistols small enough to make excellent concealed carry guns.