Sphinx SDP Compact Alpha 9mm Pistol

posted on October 3, 2014

Sphinx Systems, Ltd. of Switzerland has a long history of precision manufacturing. Originally founded in 1876 as a tooling company, Sphinx developed its first CZ-75-based semi-automatic pistol in the mid 1980s. A decade later, after its acquisition of Industrial Technology & Machines (ITM), the company launched its finely crafted models AT 2000 and AT 3000 pistols. They quickly became popular options for tactical and competition shooting. However, the price tag for these pistols is prohibitive to the average shooter, often running up to and over $3000.

In 2010, SPHINX Systems decided to join forces with the KRISS Group to bring a new pistol line to the American shooting market. The Sphinx SDP series of pistols were designed to provide the same level of precision and craftsmanship as earlier models but at a more affordable price point. This review takes a closer look at the compact Alpha model chambered for 9 mm.

The Sphinx SDP is a short-recoil operated, locked-breech semi-auto pistol. It’s constructed using mixed materials, which reduces the cost of the gun while maintaining its accuracy and reliability. The slide, barrel and other small key components are made of steel. The upper half of the frame, which supports the slide and houses the firing group, is constructed of aluminum. The grip frame and trigger guard are molded from a high-impact polymer.

The machined steel slide is beveled at the muzzle to give it a nearly triangular profile for easy holstering. Along with front and rear cocking serrations, the slide has a generous ejection port for reliable function. When a round is chambered, the edge of the cartridge base is visible through the ejection port between the slide and the breech. The extractor has a raised surface that acts as a tactile loaded chamber indicator. Like other CZ-inspired pistols, the slide is supported by full-length guide rails located inside of the frame which provides for added support and a narrow slide profile. The slide has been treated with a tough TiAIN finish to provide protection from corrosion and wear. The sights consist of a white-dot front sight and a dovetail serrated-face square notch rear sight that can be drift adjusted for windage.

The aluminum portion of the frame houses the recoil assembly, the firing group, and it features a milled-in accessory rail for lights and lasers. The recoil assembly consists of a full-length steel guide rod which supports a single recoil spring. The rounded steel bow trigger is deeply curved with a lightly serrated surface. In double-action mode the trigger required 11-pounds of trigger pull to cycle, according to a Lyman's digital trigger gauge. In single-action mode, the trigger pull dropped to 3-pounds 5-ounces with a crisp break and a short trigger reset.

The SDP’s low-profile controls include a slide stop located on the left side of the frame and an ambidextrous decocking lever. The abbreviated exposed hammer is serrated along the top edge for cocking but rounded so that it sits flush with the slide when resting in the fully forward position. When the slide is cycled, the hammer is fully cocked for single-action fire. Depressing the decocking lever drops the hammer forward into what looks like a half-cocked position. This sets the hammer away from the firing pin for safe carry. A generous beavertail extension from the aluminum portion of the frame protects the shooter's hand from the hammer.

The lower frame, including the trigger guard and grip frame, is a single piece molded from black polymer. The trigger guard is undercut to allow for a higher, more comfortable grip and the front edge has been molded to form a finger rest. The reversible, round-button magazine release has a serrated surface for positive function. The front of the grip frame has subtle finger grooves and a pebbled surface for improved traction. The grip is enhanced with a removable wrap-around soft rubber back strap system that allows the user to adjust the grip shape and thickness. The pistol ships with three inserts to choose from.

The Sphinx SDP made a positive first impression as it was removed from the shipping container. The pistol was spotlessly clean, lubricated and demonstrated a high level of craftsmanship and attention to detail. It proved to be one of the tightest production semi-auto pistols I've handled. There were absolutely no mysterious rattles, the slide showed no perceptible side-to-side movement, and the slide was as smooth as glass to cycle right out of the box. Unlike some companies who are cutting corners these days by skimping on accessories, Sphinx shipped this pistol with a usable hard case, three 15-round steel magazines, a magazine loader, and an aluminum rod cleaning kit.

With a barrel length of 3.70-inches and an unloaded weight of 27.5-ounces, the SDP felt well balanced during informal off-the-bench testing at the range. The grip was comfortable, the sights were quick to acquire, and the pistol generated a moderate and manageable level of felt recoil. The trigger was excellent with a smooth, light pull. The SDP was tested with 9mm ammunition ranging from practice grade full-metal jacket rounds to hot +P defense loads without a single malfunction in the course of testing.

To take advantage of the SDP's accessory rail for home- and self-defense applications, Streamlight's new compact TLR-G green laser and light module proved to be an excellent match for the pistol. Weighing just 2.8-ounces, the TLR-G features a 510-530 nanometer direct-drive green laser. This technology provides a bright, clear, long-distance laser sight point in environmental temperatures ranging from -20°F to +120°F. The C4 LED light provides a peak beam intensity of 115 lumens. Using a single CR2 lithium battery, the TLR-G will provide illumination for 4-hours using just the laser, 1.75-hours with the light activated, or 1.25-hours using both.

Although the SDP won me over well before the bench rest testing started, the formal 5-shot groups fired at 25-yards clearly demonstrated this pistol’s target shooting pedigree. Generally speaking, if a compact pistol can produce groups that hover around 3-inches in size at this distance, it's safe to say the gun is shooting accurately. The best 5-shot group of 1.94-inches was produced using Hornady Critical Duty 135-grain Flexlock loads. The Hornady round also produced the best group average of 2.14-inches. Double Tap 115-grain +P jacketed hollow points averaged 2.26-inches, followed by Federal Premium 147-grain Hydra-Shok jacketed hollow points at 2.44-inches. The high quality and tight tolerances of the pistol make a real difference in down-range accuracy.

The Sphinx SDP Compact Alpha 9mm semi-auto is one of the best out-of-the-box pistols for accuracy and shooter comfort that I've had the pleasure of working with. Although the SDP's suggested retail price is almost double that of some of its competitors, it runs like a custom gun that should cost even more. Sphinx has succeeded in producing a compact 9mm that can move comfortably between target competition and defensive applications without any additional tweaks or modifications required. It's one of those rare pistols that is worth more than it costs.

Technical Specifications

Manufacturer: Sphinx Arms (sphinxarms.com)
Distributor: Kriss USA
Model: SDP Compact Alpha
Action: Double-Action/Single Action
Caliber: 9 mm
Slide: Steel, Matte Black TiAIN Finish
Upper Frame: Hard-Anodized Aluminum
Grip Frame: Black Polymer
Grips: Polymer with Soft Synthetic Inserts
Sights: White Dot Front, Drift Adjustable Rear
External Safety: Ambidextrous Decocking Lever
Magazine Release: Reversible
Barrel Length: 3.70 Inches
Overall Length: 7.40 Inches
Height: 5.35 Inches
Width: 1.06 Inches
Weight: 28.18 Ounces
Capacity: 15+1 Rounds
Twist: 1:10” RH
Rifle Grooves: 6
Accessories: 3 Grip Inserts, 3 Magazines, Magazine Loader, Cleaning Kit, Hard Case, Lock, Owner's Manual
Suggested Retail: $1,295


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