The Army Has Been Buying Alternative “Barrier Blind” Hollow-Point Ammo For Its New Pistols

The U.S. Army has been buying a second type of hollow-point round for its new 9mm Sig Sauer M17 and M18 pistols,  which are also set to eventually become the standard sidearms across the rest of the U.S. military. The new cartridge is “barrier blind,” meaning that it can penetrate through certain types of obstacles, such as a window or a plywood door, first without expanding and losing much of its stopping power.

It’s not clear how long the Army has been buying these rounds or if it has begun issuing them for operational use yet. The service did officially designate the cartridge as the XM1196 in March 2019, according to information from the web-based version of the U.S. government’s Federal Logistics Information System, or WebFLIS. Versions of Sig Sauer’s P320 pistol series won the Army’s Modular Handgun System (MHS) contract in January 2017 and, despite the need for some additional work on the design, the service has been steadily issuing them to operational units since December of that year. This month, Sig announced that it had delivered 100,000 M17s and M18s to the U.S. military so far.

The Army’s decision to purchase the full size and compact variants of Sig Sauer’s P320, which it designated M17 and M18, respectively, also came along with the acquisition of an entirely new family of 9mm ammunition. This included the M1153 hollow-point, which Winchester designed for the service based on its T-Series

An M18 pistol, which is the compact version of the M17, with its slide fully locked to the rear., US Air Force

Winchester has been tight-lipped about exactly how the M1153 differs from the other members of the T-series. It was “designed to maximize performance based on the government specification set out in the RFP [request for proposals],” Glen Weeks, Winchester Ammunition’s Director of Government Contracts and Specialty Products, told American Rifleman magazine earlier this year.

Unfortunately, WebFLIS does not name the company or companies that the Army has been working with on the alternative XM1196 or offer any details about the new cartridge’s specifications, though it does list a unit price of 31 cents per round. That the service is buying them at all would indicate that it is not entirely satisfied with the barrier penetration qualities of the existing M1153.

Magazines for the M17 and M18 pistols loaded with M1153 hollow-points., US Army

While we don’t know the specifics about the XM1196, there are a number of commercially available 9mm rounds that are sold as having improved barrier penetration characteristics. This notably includes Hornady’s Critical Duty line, which the company specifically describes as “barrier blind” and that has already entered service with the Federal Bureau of Investigation (FBI).

Typical hollow-point bullets function by expanding into a mushroom shape as they hit their target, transferring more energy and creating larger and more devastating wound cavities. The Critical Duty design traces its roots back to the 1990s and is an evolution of concepts that involved inserting plastic plugs into the center of hollow-point bullets to give them better ballistics and penetration. 

Filling the gap in the center of the bullet also prevented it from getting stuffed fall of other material as it passed through barriers, such as windows or even heavily clothing, which could prevent proper expansion. Unfortunately, these plastic-tipped rounds often had had exactly the same problems, often having terminal effects more in line with standard full metal jacket or “ball” rounds.

The Critical Duty design uses what Hornady calls “Flex-Tip” technology, something it has patented, which uses a more elastic compound as the filler instead of a hard plastic tip. This helps its “FlexLock” bullets retain a more uniform shape for penetrating through material such as plywood, thin sheet metal, and auto glass, and not get otherwise plugged up, but then still reliably deform when they hit their targets, creating the desired expansion. 

The video below shows the internal design of the Critical Duty rounds and offers some demonstrations of its penetration capabilities.

The complete rounds are also designed in such a way that the lead core is better “locked” inside its metal jacket so that it doesn’t squirt out the front after passing through a hard object, also known as jacket separation. This, again, helps ensure that the entire bullet remains intact during flight and functions as intended before and after it hits the target. Testing has shown that the bullet consistently maintains at least 60 percent of its total weight after penetrating barriers.

Critical duty first hit the market in 2013. The FBI subsequently put it through its famously rigorous ballistic testing and adopted it as a standard-issue round last year.

No matter what the round’s particular specifications might be, if the Army adopts the XM1196 for issue on a general basis, or even a limited one, if it hasn’t already, the rounds may find their way into other guns beyond the M17 and M18. Other services and the U.S. special operations community might also already be interested in the cartridge.

The details available on WebFLIS indicate that the Army has already deemed it suitable for use in existing standard-issue M9 and M11 pistols, as well as various Glocks and Sig Sauer P226s that various U.S. special operations and other specialized units use. The venerable Heckler and Koch MP5 submachine gun is another one of these associated “end items” for the new rounds, too. At the time of writing, the B&T APC9 PRO submachine gun, which the Army announced it was buying this year for VIP protection details was not on the list.

A member of the US Army fires an MP5 submachine gun., US Army

The Army’s acquisition of a second hollow-point round for the M17 and M18 does also raise questions again about the general legality of these cartridges in actual combat. The service has said that the existing M1153 is approved for general combat use, despite the prohibition on the use of expanding ammunition in the Hague Convention of 1899

It is worth noting that the United States has never signed or ratified that treaty, but has typically abided by its provisions, including not issuing hollow-point ammunition for previous sidearms on a general basis in the past. That being said, the U.S. military, and special operations units especially, due use hollow-point and fragmenting ammunition in certain cases based on the position that it is appropriate to use these rounds in combat when there is a “clear military necessity.” These types of cartridges are particularly well suited to hostage rescue and close-quarters-combat scenarios where there are concerns about over-penetration putting friendly forces or innocent bystanders at risk.

Hopefully, more details will emerge about the XM1196 and its capabilities in the near future. What is clear is that the ammunition selection for the M17 and M18 pistols, as well as other 9mm weapons across the U.S. military, is still growing to include more types of specialized rounds.

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Joseph Trevithick

Deputy Editor

Joseph has been a member of The War Zone team since early 2017. Prior to that, he was an Associate Editor at War Is Boring, and his byline has appeared in other publications, including Small Arms Review, Small Arms Defense Journal, Reuters, We Are the Mighty, and Task & Purpose.