P320 ASP Part 1

Sig Sauer’s 4.5mm P320 ASP Part 1 Part 2 Part 3

The U.S. Army’s new official standard issue sidearm

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has an official CO2-powered training counterpart!

by Dennis Adler

The Sig Sauer P320 ASP (right) is the first semi-automatic .177 caliber air pistol to utilize a 20-round belt magazine. Designed to look and feel like the P320 centerfire pistol (left), the ASP’s weight and trigger pull are virtually identical offering recreational shooters, professionals and competitive shooters another outstanding training tool to hone their shooting skills.

The new Sig Sauer P320 ASP is a historically significant airgun for several reasons; first, it is being introduced on the heels of Sig Sauer having been awarded a U.S. government contract in January of this year to replace our nation’s aging Beretta Model 92 Series semiautomatic pistols with the P320 as the standard issue sidearm for the U.S. Army. The Beretta M9 has been in service since 1985 when the Italian armsmaker became the first foreign branded handgun to be adopted as a standard issue pistol for the United States military. In 1985 the selection of the 9x19mm Beretta M9 (M9 is the military designation for the 92FS) ended a 74 year succession of Colt .45 ACP 1911 models being carried by all branches of U.S. military and a significant number of government agencies. Originally developed by John M. Browning and Colt’s to be the official sidearm for all branches of Government service, the M1911 was officially adopted on March 29, 1911 as the “U.S. Pistol, Automatic, Calibre .45, Model 1911” succeeding a series of .38 caliber Colt double action revolvers that had replaced the Colt Single Action Army in 1889. The Colt’s Patent Firearms Mfg. Co. had continuously won U.S. government contracts for military sidearms since 1855, when the 1851 Navy was adopted, and thus the c.1985 Beretta M9 was to become the first standard issue U.S. military sidearm not manufactured by Colt’s in 130 years! The Sig Sauer P320 is only the second.

Sig Sauer’s ASP models are built as training guns and are simplified in their rugged construction by eliminating components that serve no function for training, such as an opening ejection port, which is molded into the slide. The right side slide release is also a non-functional part. The white dot sights duplicate those of the centerfire P320 models.

Sig Sauer has been providing weapons to the U.S. military and government agencies outside of the standard issue sidearm category for many years (such as the P226 carried by Navy SEALS). Sig Sauer had already developed the P320 modular design handgun to meet the demands of 21st century military and law enforcement. Introduced in 2014, it was Sig’s first polymer frame, striker fired model. When the U.S. military started searching for a handgun to replace the Beretta M9, it was determined that it would have to be a modular handgun system. The Sig Sauer P320 already had that advantage. Competing against finalists Beretta, Glock, and FN USA for the $580 million contract, Sig Sauer clearly met the Army Modular Handgun System (MHS) requirements. This included adaptability to different end users, such as variations in hand size, and an ability to change the frame, barrel, and slide length, as well as caliber, if so desired, while maintaining a single modular platform. The P320 exceeded those requirements within its original design; in short, with one standard size 9mm Sig Sauer P320 and appropriate accessories, the pistol can be quickly reconfigured from a full-size duty gun to a compact or subcompact pistol by changing frames, slides and barrels, as well as changing only frames to properly fit small, medium and large hand sizes.

To best understand the basis for the P320 ASP you have to see the components that make up a centerfire P320 model. For all intents and purposes the P320 is the small component at the top, housing the firing mechanism and trigger. From a purely legal standpoint, this is the gun; everything else you see here is an interchangeable component; the very definition of a modular design. You only need one P320 mechanism to make any of these combinations work. The P320 ASP is based solely upon the full-size model as a single, complete gun with no interchangeable capability. Could Sig Sauer offer a compact and subcompact CO2 version? It is very likely if the full-size model is a success as a training gun.

The military version can also accept a number of accessories and attachments such as silencers, and extended capacity magazines. While the gun can also be changed from 9x19mm (9mm) to .357 Sig and .40 S&W, the Army chose to retain the same caliber as the Beretta M9. The MHS Program provides for the delivery of both full size and compact P320 models over a period of ten years with the new military sidearms being built in the United States at Sig Sauer’s manufacturing facilities in New Hampshire. The timing of this contract could not have been better for Sig Sauer, which was already developing the P320 as its newest ASP CO2-powered air pistol. Introduced this month, the P320 ASP is intended as both a training and sport shooting pellet-firing semi-auto with blowback action and a first ever belt-fed 4.5mm pellet magazine with a capacity of up to 20 rounds.


I have a somewhat unique perspective on the Sig Sauer P320 ASP having tested the P226 ASP last year, and also one of the first production 9mm P320 models back in 2014, so I am quite familiar with both the cartridge-firing model and Sig Sauer’s slightly minimalist approach to the ASP pellet firing models. The P226 ASP was designed to have the look and feel of the centerfire models with similar weight and trigger pull for training purposes.

The Sig Sauer Advanced Sport Pellet (ASP) air pistols are built to resemble the centerfire model but do not share all the functions of the cartridge-firing models, only those deemed necessary for training purposes. The weight, balance, trigger and blowback action all contribute to that goal. 
The ASP has matching front and rear slide serrations. The slide can be racked to chamber the first round but does not lock open on an empty magazine. Since the slide does not lock back the left side slide release is a different shape than the centerfire model and functions as a manual safety. The shape of the magazine release, size and operation are identical to the cartridge model, as is the trigger configuration, triggerguard and dustcover accessory rail. The P320 ASP is offered in black and coyote tan which will be available later this year.

The Sig Sauer Advanced Sport Pellet (ASP) blowback action air pistols are built to the same standards as the company’s premium pistols and rifles (the latter being Sig Sauer’s MCX and MPX ASP semiautomatic pellet rifles), to ensure that professionals who train with these airguns experience exceptional performance and true hands on operation. Like the P226, the new P320 ASP is offered in black or Coyote Tan (Coyote Tan will be out a little later this year), but unlike the P226 models, which use a reversible dual 8-round magazine (for a total of 16 shots in one magazine) the P320 ASP ups the ante with a MCX/MPX-inspired rotary belt-fed pellet magazine. The P320 still utilizes a separate CO2 chamber, accessed by lifting the backstrap panel, but considering the new magazine design and its 20-round capacity, not such a bad tradeoff.

The most interesting feature of the new Sig Sauer P320 ASP is the magazine which utilizes a belt-fed system to hold 20 rounds for the highest capacity of any pellet-firing semi-auto CO2 pistol.

In terms of weight, balance, trigger design, sights, and operation, the only thing missing is a few minor operating features found on the centerfire models, leaving the P320 ASP as a basic training gun with benefits.

In Part 2 the ASP is compared to the full-size 9mm P320.    

3 thoughts on “P320 ASP Part 1”

  1. will be interesting to see the shooting evaluation. Not sure how many shots one co2 will give , maybe one magazine of 30 with blowback. I am not a fan of da only handguns ,and would have preferred a more traditional da/sa pistol for the military, or even a striker fired pistol. SIG ,with its’ airgun line still talks a big game , but likes to go for the lower end market ,with non functioning molded in parts and sights. If they want to live up to their name , they should up the level and the price point of their airguns.

    • For the most part I agree with your evaluation, but Sig Sauer is dedicated to a specific style of training gun (much like Umarex and Walther was with the CP99 over 17 years ago), and there may be a very no-nonsense mind set here, whereas many of us, myself included, prefer a full function air pistol for training exercises, like the Umarex S&W M&P40. The concept behind the basic training theory with Sig Sauer is more about fundamentals of handling, draw, racking the slide, sighting and firing, than working over every aspect of the gun’s operation, including disassembly, like the M&P40. It is designed more for a training point in Sig Sauer’s view than for a price point, although it is reasonably priced. I will demonstrate some of this in Part 3 of the P320 articles. As to how many shots on one 12 gr. CO2 cartridge with a 30-round magazine, we’ll see.

      • Part of training is drawing and firing , but having inert controls and giving others different functions, confuses muscle memory. I would prefer an understudy like the S&W MP 40 ,that does this properly ,and for about the same price point. That is what I like about the 1911 airguns. Totally identical understudy air pistols. Sig will probably capture some practice market, just because the military is using the 320 and other agencies will follow. The drum mag is innovative , but I think it would be better in subguns or carbines

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