We have another pair of projectiles today: one AP and another looking for a purpose.

The story starts with US Army ordnance engineer Abraham Flatau. One of his earliest experiments with tubular projectiles came about when he was trying to develop an improved grenade launcher projectile. The issue 40x46mm grenades had a high trajectory and poor fragment distribution. Flatau’s Ring Airfoil Grenade (RAG) concept meant to flatten the trajectory without increasing recoil. After playing with 2-inch, 2.5-in, and 2.75-in prototypes, Flatau settled upon the 2.5-in size. You can see the original RAG patent here:


However, the 40x46mm grenade and its launchers were too entrenched to be replaced by the RAG and its dedicated launcher. That didn’t stop Flatau from playing with new variations of the design. These were intended for riot control. The “Soft RAG” dispersed CS irritant compound upon impact. It was standardized as the M742 64 mm CSI Riot Control Projectile.


Its fraternal twin, the “Sting RAG” was meant for direct fire against a protestor. It was standardized as the M734 64 mm Kinetic Energy Riot Control Projectile.


Sting RAG and Soft RAG

The Sting RAG and Soft RAG were launched using the 64mm M234 Riot Control Projectile Launcher, mounted to the muzzle of an M16A1 rifle. The projectiles were fired using a 5.56mm M755 Blank grenade cartridge.

M234 Riot Control Projectile Launcher

Flatau’s next ring airfoil application was for small arms cartridges. He envisioned launching multiple ring projectiles from a single cartridge. The experimental loadings focused upon the .45 Auto, first using three 20-grain .40 caliber zinc rings in a sabot. The latter were considered to have insufficient mass, and low/inconsistent velocity. The next attempt used a pair of 35-grain .40 caliber rings in a sabot. These clocked at 1,450 fps, and gave a two foot impact pattern at ~25 yards.


Flatau followed up with a full-caliber, single projectile variant for the .45 Auto. His main goals were to reduce recoil and provide improved penetration, specifically the ability to defeat the Army’s new Kevlar body armor and helmet. Flatau filed his initial patent application in October 1979, a revised application in June 1983, and received US Patent #4,742,774 in May 1988.


During the early days of the full-caliber tubular .45 design, Flatau was working at Edgewood Arsenal. He quit government service in 1980, worked privately for 18 months, and then returned to work at Aberdeen Proving Ground’s Human Engineering Lab in late 1981. Before his hiatus, Flatau had contracted with Guilford Engineering Associates, Inc. (GEA) to produce prototype ammunition. GEA’s David Findley had also worked with multiple ring projectile ammunition in the past, specifically .50-caliber rings in a 12 gauge hull.

Multiple variations of the single projectile/full caliber variant were tried, including 9x19mm, .45 Auto, 9mm Winchester Magnum, and .45 Winchester Magnum. (Later, there were even .38 Special and .357 Magnum variants.) Instead of using a plain copper ring, they also used a sharpened steel insert to help slice through barriers like Kevlar.

The plastic obdurators were later elongated to extend through the center hole, past the tip of the steel insert of the 9mm and .45 variants. This was to prevent damage to the sharpened steel tip as well as the feed ramp of the firearm.

According to some sources, a demonstration was performed for some top brass involving the GEA .45 Auto round and a goat wearing a Kevlar helmet. It went in one side and out the other. Reportedly, some of the officialdom lost their lunch, and that was the end of official US Army interest in the round.

You might notice the ANSB variant in the photos. These were not tubular bullets. ANSB stands for Annular Nose, Solid Base. Effectively, they were hollowpoint bullets with a steel insert. The ANSB was reportedly the brainchild of Edgewater Arsenal personnel skeptical of the tubular projectile.

GEA’s tubular and ANSB variants did reportedly see limited use by the FBI and other federal agencies. It apparently gained the unofficial nickname “Cyclone.” A writer for “Soldier of Fortune” magazine even suggested that the Cyclone bullets were to blame for some of the BATF’s friendly fire casualties during the Koresh compound raid in Waco, TX.

1987 ad

In the mid-1980s, PMC somehow heard of the ring airfoil pistol bullets, and without Flatau’s permission, revised the design to remove the steel cutting insert. The first run of .38 Special Ultramags were labeled as ‘armor-piercing’ because of their use of brass. This delayed the introduction from 1986 to 1987 when the copper variant was released. Circa 1988, PMC added a .44 Special load.

Unfortunately, PMC had no idea of how to market the bullets and they were eventually pulled from production in the early 1990s. Oh yes, Flatau ultimately came to a agreement over royalties with PMC concerning patent infringement.

Sectioned .44 Special Ultramag

1 Comment

  1. Tom Stone says:

    Thank you for this wonderful series of posts.
    I suspect the best ( And least likely to be adopted) means of increasing lethality would be to double the training budget.


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