In the early 1980s, the Marines were looking into light antitank weapons. They had the M72 LAW and the AT4, both of which were solid disposeable rocket launchers. However, they were limited to a single warhead type, and Vietnam had showed the utility of reusable systems, like the old recoilless rifles. So they went shopping. They settled on a variant of the B-300 rocket launcher, originally developed in Israel. A number of changes were made, resulting in the Mk. 153 SMAW.
The SMAW is a somewhat unique “two-piece” launcher. The front section of launch tube also includes the grips and sighting system. The rear section of the launch tube doubles as a storage container for the rocket. This section gets attached to the front section to “load” the SMAW.
The SMAW originally came with an integral spotting rifle. This fired a 9mm tracer round, specially designed to match the trajectory of the rockets. This round is a 9×51 mm cartridge, which can be thought of as a 9mm round inserted into a necked-out 7.62x51mm casing. Curiously, it’s also propelled by a .22 Hornet blank cartridge inserted into the 7.62x51mm cartridge, as seen below.
Although it’s a simple rocket launcher, the SMAW does not have a wide variety of warhead options available. There’s a HEDP round, an HEAA round, and a thermobaric round. And that’s it. The HEAA (anti-armor) round has a standoff rod, and is rated for 600 mm RHAe penetration. It is not, however, a tandem warhead. The HEDP round is not airburst capable. The thermobaric round is quite a bit heavier than the other two, but proved to be effective in both offensives in Fallujah. Like most other unguided rocket launchers in its class, the SMAW has an effective range of about 500 meters.
The Mod 2 SMAW replaced the spotting rifle with provision for an electronic sighting system with laser rangefinder, which is easier and faster to use. It’s also lighter, weighing 13 lbs. compared to the Mod 0’s 16.5 lbs.
The lack of warhead options hurts the SMAW when compared to its contemporaries, especially the Carl Gustav. The Carl Gustav also has about twice the range of the SMAW. Interestingly, despite the recent introduction of the SMAW Mod 2, the USMC has also opted to follow the US Army in purchasing the Carl Gustav for issue to its rifle squads. No word yet on whether or not it will replace the SMAW for Marine combat engineers.
Really though, there’s not much of a reason to have both of the two systems. I’ll be interested to see if any comparative testing gets done, but the Carl Gustav is more popular, and has the round variety, not to mention the better range. So that’s what I’d expect would win out overall.