The SIG Rattler has all of the makings of a powerful weapon. We asked a former U.S. Marine and a true firearms expert to break down what the means for U.S. special forces now and in the future: SOCOM had been looking for a new personal defense weapon for the last five years, and now it has finally found one. SOCOM recently announced the adoption of the SIG Rattler as their Personal Defense Weapon (PDW) of choice.
Over time SOCOM has tested a number of platforms, but according to it, only SIG Sauer’s entry met all the standards.
“After years of continuous market research, USSOCOM HQ has concluded that Sig Sauer is the only vendor that can fulfill USSOCOM’s need for the Commercial PDW requirement,” SOCOM said.
The procurement contract will be for five years at a fixed price.
“USSOCOM HQ has been researching and reviewing different systems since 2017. We have meticulously reviewed each system for technical acceptance and whether it fits the commercial definition,” SOCOM’s Notice of Intent read.
“Except for Sig Sauer, the vendors did not meet the technical requirements, and/or the weapons do not meet the commercial definition. Due to the nature of this particular effort, USSOCOM cannot procure PDWs that are prototypes, under development, not in production, are in limited production, or will be in general production in 1-2 years from now,” SOCOM added.
Inside the SIG Rattler
The SIG Rattler premiered in 2017 and is a mini version of the SIG MCX. (The SIG MCX family also includes the Spear, which was adopted as the XM5 in the recent Next Generation Squad Weapon (NGSW) contest.) The MCX system is a short-stroke gas piston gun that has become extremely popular in the last few years. The Rattler takes the MCX platform and shrinks it. They trimmed the barrel to 5.5 inches with a short M-LOK handguard and folding stock system.
The folding stock is a minimalist, fairly simple, rugged metal stock. SIG went above board to make the weapon incredibly compact. This includes the pistol grip, which is trimmed and rounded for easy concealment. Short-stroke gas piston systems tend to work exceptionally well with short barrels.
The weapon can be fired with the stock folded. Unlike the AR-15 design, the buffer system is kept inside the upper receiver, much like the AR-18. This allows for a very compact weapon which seemed to be the goal of the SOCOM PDW project. The Rattler comes in both 5.56 and 300 Blackout, and according to the Notice of Intent, SOCOM is purchasing both calibers.
The Rattler system and the SIG MCX, in general, are compatible with standard M4/M16/AR 15 lower receivers. Based on the project’s history, it seems like SOCOM was looking for an upper receiver group and buttstock kit to outfit M4A1 lowers. The Notice of Intent states they are purchasing complete weapons.
The package also includes suppressors, magazines, cleaning kits, quick barrel change kits, force-on-force training kits, and training and instruction on the weapon.
What’s a PDW
Personal Defense Weapon is a term that came around originally in the early 1990s. It came to describe a new class of SMG-sized weapons firing PDW calibers. The P90 and MP7 are the most famous examples of a classic PDW. The SIG Rattler doesn’t necessarily fall into that category, as it’s much more rifle-like, but still defines the more modern PDW.
The SOCOM project and the Rattler seem to be SOCOM’s attempt at finding an SMG-sized, concealable platform for troops pulling special missions. These won’t be the new service weapon of SOCOM by any means, but likely a niche weapon for roles where secrecy is necessary and maintaining a low profile is critical.
A PDW like this doesn’t offer you the same range, penetration, or capability of a rifle but outperforms a pistol or submachine gun by a large margin.
The 5.56 and .300 Blackout calibers
SOCOM will purchase both the 5.56 and the .300 Blackout for use with the SIG Rattler.
AAC developed .300 Blackout round from the ground up for use from short barrels. The round reaches its peak potential from barrels as short as nine inches. The use of a .30 caliber projectile also makes it easy for shooters to choose between a supersonic or subsonic projectile.
The lighter-weight supersonic projectiles offer greater range and penetration but are not as quiet when suppressed. The heavier subsonic rounds don’t offer the same range and penetration, yet, they are incredibly quiet when suppressed. So, the .300 Blackout makes a lot of sense with the SIG Rattler, especially when suppressed.
On the other hand, the 5.56 round doesn’t make a ton of sense. When Remington designed the .223 round that eventually became the 5.56 NATO load, they optimized it for a 20-inch barrel. Every inch you shave off creates rapidly declining performance. The Rattler’s barrel will be 5.5-inches long, so I wouldn’t be surprised to see keyholing and subpar performance as well as limited to no fragmentation due to the lower velocity of the round.
The round is also going to be very loud, with a lot of muzzle flash and concussion without the use of a suppressor. Although the 5.56 is much more common and available in the military pipeline than .300 Blackout, its inclusion is still peculiar. I’m curious to know how the 5.56 weapons will be used versus other options like the Mk-18.
What about the LVAW?
The SIG MCX is already in the pipeline for the LVAW project. The weapon has been used by Delta Force and is one of the smaller variants of the MCX. It’s quite similar to the SIG Rattler, but there are differences: The Rattler’s barrel is a bit shorter. The LVAW uses a 6.75-inch barrel compared to the 5.5-inch barrel of the Rattler. The LVAW also features a different handguard, stock, and pistol grip. The differences are minor but worth noting.
Will the Rattler replace the LVAW? I’m not sure, but they seem to have the same mission.
SIG just keeps winning. First the NGSW, then the MHS, and now the PDW project. They don’t lie when they say they are a total systems provider.
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