The ASAI One Pro Handgun

By R.K. Campbell

The ASAI One Pro pistol may be the finest example of Swiss precision this author has yet seen. Comparing this .45 caliber handgun to the SIG P210 or any other handgun doesn’t leave the One Pro coming up short. The One Pro is now out of production and only a few were imported. When originally offered for sale by Magnum Research the pistol sold for less than six hundred dollars and today examples in good condition command twice that sum. In this review we will look at some of the reasons the One Pro is held in such high regard. The pistol was designed by European designer Martin Tuma and manufactured by Oerlikon. The pistol features a double action first shot trigger, a well-designed and easy to manipulate slide lock, an equally handy decock lever, excellent combat sights and custom grade slide serrations. The pistol is a double column magazine .45 ACP caliber handgun with an 11 round capacity. The pistol is similar to the AT 88 and other Tuma designs, but it is an improvement over earlier pistols.

In common with the CZ 75 handgun that the One Pro seems based on, the slide of the One Pro rides inside the frame rails. This results in a lower bore axis than is common with double action handguns. While there are advantages to the low profile CZ the slide is more difficult to rack as a result of this design. The One Pro addresses this difficulty with seven diamond pattern studded cocking serrations on each side of the slide. The slide is taller than the CZ 75 while remaining a low profile inside of the frame. The full length rails maintain contact with the receiver and increase accuracy potential in terms of intrinsic accuracy. The One Pro is of all steel construction, which means that it is about as heavy as a Government Model 1911A1 .45. In modern times this weight would limit institutional sales. Supposedly a lightweight frame pistol was planned but I have never seen one.

The pistol relies upon proven locked breech short recoil principles. There is no barrel bushing and the One Pro relies upon angled camming surfaces for unlock. The barrel hood butts solidly into the slide. There is a positive firing pin block or drop safety. The tall sights seem dated and while they offer a good sight picture a more modern handgun would probably use low profile sights. Just the same, the overall fit and finish of the pistol is excellent and few if any handguns surpass the feel of quality although a few equal the One Pro. The sights ride in a wide dovetail and there is a nicely turned rib that runs along the top of the slide. The machining of the slide is first class and clearly took considerable time to execute. This is not a handgun designed to be produced economically, but a handgun designed to promote excellence.

The frame is nicely finished with the front and back strap each nicely checkered to aid adhesion. The trigger guard is conventional and the trigger is rounded rather than hooked as in other CZ clones. The trigger guard will accommodate gloved hands. The grip frame is engineered to accept a ten-round magazine. The One Pro is a 10 +1 or 11 round .45 ACP pistol. This is quite an engineering feat. The grip frame is no larger than a 9mm CZ 75, as an example, and considerably smaller than a Glock 21 .45 caliber handgun. However, the single bone of contention with the One Pro comes with this grip frame. The bevel at the front strap is not comfortable for all shooters compared to the original CZ 75. The grip panels are skimpy for the frame and seem out of place on such a well-made handgun. The grip panels are roughened for abrasion and do the job but little else. The grip frame is slightly recurved near the base, perhaps in a portion of the Divine Angle. The grip frame isn’t uncomfortable but the angle of the bevel could have been more rounded.

Ergonomically, the decock lever, the magazine release and the slide lock are all within easy reach without resorting to shifting the grip on the handgun. The pistol has a good heft and a good natural point. The One Pro is heavy but sets well in the hand. This weight serves in good stead when firing heavy loads. While lighter .45 caliber handguns are not painful to fire after a few magazines the jolt of recoil begins to take its toll. The One Pro is comfortable to fire in extended training sessions. As an example, the powerful Speer 200 grain Gold Dot +P was used in the One Pro and the recoil was not severe, in fact, downright comfortable. Yet this load breaks 1,000 fps in the One Pro’s 4.5 inch barrel. The pistol is well made of good material and seems smooth in operation but the true test of the handgun is in firing.

When firing the One Pro a consideration was the trigger action. The double action mechanism of the One Pro is the lightest and smoothest I have tested in any handgun. The double action trigger compression was measured on an electronic scale and the trigger breaks at 5 pounds 11 ounces. This is lighter than many single action triggers. Yet, when the trigger is pressed the trigger both cocks and drops the hammer with less than six pounds of pressure. There was some concern that the action might not be sufficient to crack all primers, but this was not the case (some brands of ammunition use harder primers than others). The One Pro never failed to ignite the primer. The single action trigger compression is less than three pounds. When using such a light trigger action the compression felt like a finely tuned target handgun. This pull weight is far too light for a service pistol, in my opinion. The shooter that wished to use such a handgun for personal defense would be advised to adhere to this handgun and no other and to train hard and then fire the pistol often. During the firing test on more than one occasion the author doubled, firing two shots when I intended to fire a single shot, with the single action press. After some acclimation the trigger was mastered sufficiently to rate it controllable. In off-hand combat firing the light trigger isn’t really an advantage as the light press sometimes causes even a trained shooter to clutch the trigger. When firing for groups off of the benchrest the situation was different. The good sights and light trigger action aided in obtaining excellent accuracy. Firing at 25 yards from a solid benchrest, the One Pro sometimes delivered five shot groups hovering around an inch. Almost always human error intervened and the average groups opened to 1.5 to 2.0 inches. Just the same, the One Pro is a very accurate handgun. An observation was made that the single action trigger of the One Pro is free of the modest backlash often exhibited by CZ 75 type trigger actions.

When running combat drills the One Pro showed excellent results. Drawing and engaging targets at 5, 7 and 10 yards, hits were well centered. The transition from double action to a single action trigger presented no difficulty. When performing speed reloads the tapered high capacity magazines allowed rapid replenishment of the ammunition supply. The pistol functioned well with CCI Blazer ball ammunition and brass cased American Eagle ammunition. 230 grain ball loads strike just above the point of aim. This is a good service setting, with the slight off-set easily accounted for at close range. The pistol is dead on with this zero at 50 yards and will probably prove accurate at extended handgun range.

All told, the One Pro is an interesting handgun with much to recommend. It is accurate, reliable, and well made of good material. It is an excellent handgun on every count. While there are less expensive handguns, there are few with the pride of ownership and heritage of this handgun.