The Mosquito is a medium-size, double-action, semi-automatic pistol 90 percent the size of the Sig Sauer P226, one of the company’s most popular handguns. The package begins with a fixed, 1:16 RH-twist, 3.98-inch blued steel barrel.  

Almost annually, at least in recent years, several new cartridges have entered the market. But, much like the fashion industry, some guns and cartridges go through phases, or trends, where they have their heyday and then seem to disappear for one reason or another. Other cartridges, though, seem to have a never-ending supply of fans, and for good reason. The .22 LR is one such cartridge. Its low cost, near non-existent recoil, universal availability and accuracy make it the one of the most popular cartridge the world over, not only for hunting and competition, but for training as well. For that very reason, Sig Arms chose the cartridge for its newest training pistol.

The Mosquito is a medium-size, double-action, semi-automatic pistol 90 percent the size of the Sig Sauer P226, one of the company’s most popular handguns. The package begins with a fixed, 1:16 RH-twist, 3.98-inch blued steel barrel. To improve accuracy and protect the rifling, the barrel has a recessed muzzle crown.

The Mosquito’s aluminum-zinc alloy slide has beveled rear-slide serrations that provide excellent purchase when racking. Atop the slide are a blade front sight and adjustable rear, both with yellow-green inserts. The front sight is staked into place from the inside of the slide, while the rear sight is dovetailed into the rail. Sight radius measures 5.51 inches.

The pistol’s primary safety is a slide-mounted, ambidextrous, manual safety switch located below and to either side of the rear sight. Simply push the manual safety down to engage, and the reverse to disengage. A second safety, an integral, key-operated safety lock, is located behind the magazine. Operation is performed using the provided key. A third safety is a magazine disconnect, which requires the magazine to be in place before the pistol will fire.

Directly under the manual safety is the Mosquito’s slide stop. It has several horizontal serrations and is angled downward, making it very user friendly. Just to the front of the slide catch lever is the decocker, which allows the shooter to lower the hammer with a sweep of the thumb. The Mosquito’s double-action trigger pull weight is 13 pounds, 8 ounces, and single action is 6 pounds, 4 ounces.

Magazine capacity is 10 rounds. Because the magazine is constructed nearly entirely of metal and is of substantial weight, it drops clear of the pistol. Quick reloads are somewhat difficult because the magazine well is not beveled.

Like its larger-caliber brethren, the Mosquito has a wear-resistant polymer frame, however, it also has an integrated Picatinny rail for a light or accessory. Ergonomically shaped and stippled, the Mosquito’s grip provides excellent purchase, even with damp hands. Aiding the grip are horizontal ribs on the frontstrap. The front potion of the trigger guard also has ribs, although they are more cosmetic than functional. A beavertail protects the shooter’s hands from hammer bite. The Mosquito’s height measured 5.28 inches, its frame 1.46 inches wide and overall length 7.20 inches. With an empty magazine in place, the Mosquito weighs in at a light, 24.6 ounces. The Mosquito is available in several color combinations: black frame and blued slide; green frame and blued slide; and black frame with stainless-finish slide.

I shot five, five-shot groups from a sandbagged rest at 25 yards with each of the three brands of ammunition. The most accurate load tested was CCI’s .22 LR Pistol Match, which averaged 2.11 inches. Accuracy was respectable, considering the short barrel length. I found the Mosquito’s sight configuration a handicap while shooting for groups. Not only did the large sights overpower the target, the yellow-green inserts were more of a distraction than an asset. As a training pistol, most probably wouldn’t shoot at this distance, so the sights wouldn’t be a problem in that role. During accuracy testing, there were two failures to feed, both with different ammunition brands. No extraction problems were encountered.

After I finished shooting for groups, I put the Mosquito through its paces during some short-range drills, at a distance of 7 yards. The Mosquito emptied the 10-round magazines in short order and without any malfunctions. Because of the Mosquito’s light recoil and slight muzzle flip, follow-up shots were extremely fast. In a very short time I sent more than 50 rounds downrange. I really liked the way the Mosquito felt and pointed. Its grip thickness, angle and design fit my hand well, even though I have large hands. The Mosquito balanced well and wasn’t overly heavy, even with a fully loaded magazine.

The Moquito’s primary design purpose is that of a training device. Constructed with the same controls and feel as full-size, larger-caliber Sigs, only in a smaller, user-friendly version, the Mosquito gives users a tool to practice and grow with, both physically and mentally. Beginners will learn shooting fundamentals and proper operation fast because the fear of recoil is eliminated. This allows them to practice more frequently and for longer periods at a time, which builds confidence. When the time comes to move on to a larger-caliber handgun, the shooter will have the fundamentals of good shooting and pistol operation down pat, allowing him or her to more easily transition to the new pistol, whether duty or civilian self-defense.

The Mosquito would make an excellent addition to any law enforcement arsenal. Recruits entering police academy with little or no firearm knowledge or experience—which is often the case—would have a firearm that makes it easy to learn the basics and help them master the skills that might save their lives on the street.

In a hunting role, the Mosquito would make an excellent handgun to hunt squirrels and rabbits and rid the garden of unwanted vermin. Its compact size and light weight make it an easy carry when in the field, and its chambering is still an excellent game getter.

Sig Arms has taken the .22 LR and chambered it in a pistol that makes an excellent training and recreational tool. With its good accuracy and lack of recoil, the Mosquito is sure to find its way into training facilities, backyards and fields, all the while building confidence and accuracy, not to mention smiles.