SUBGUN COMPARISONS

By Frank Iannamico

Two popular submachine guns that are occasionally available in the Class III marketplace are the Swedish K, which was marketed commercially as the Carl Gustaf, and the Smith and Wesson Model 76. The two submachine guns are often compared to one another as the S&W Model 76 was designed to supplant the Swedish K in service with U.S. Special Forces then serving in Southeast Asia.

The Swedish K was originally designed in 1944, while the Smith and Wesson Model 76 was designed twenty-two years later in 1966. The Swedish K was still in production when the S&W 76 was conceived. The Smith 76 was intended to be an improved version of the Swedish K submachine gun, although most enthusiasts today will tell you that the Model 76 did not achieve its goal. This article is intended to compare the pros and cons of the two 9mm submachine guns.

The Swedish K

The Swedish submachine gun is known by a number of names including; the Swedish Kulspruta M-45, the Carl Gustaf or the “Swedish-K.”

The Swedish K was originally conceived by designers at the Swedish Forsvarets Fabriksverk Company in 1944. Forsvarets Fabriksverk was a rather large Swedish manufacturer of small arms, machine guns, artillery rounds and torpedoes. The Swedish K submachine gun was produced at the Carl Gustafs Stads Gevarsfaktori (factory) located in the town of Eskilstuna in southeastern Sweden. The production of the submachine gun did not begin until 1945 after World War II had ended. The 9mm submachine gun had a tubular sheet metal receiver to house the heavy bolt and driving spring. The fixed firing pin is an integral part of the bolt. The trigger and sear assemblies were contained in a rectangular housing that was permanently attached to the receiver tube by welding. The tubular steel folding stock was very well designed and sturdy when extended, and featured a rubber cheek rest. The large rear pistol style grip was fitted with wooden panels attached by two machine screws. The barrel is held in place by a large round knurled barrel nut and is easily removed for cleaning or replacement. The receiver has an index pin to insure that the barrel is always installed in the same location. The well-protected rear sight, located near the center of the receiver tube, has three flip-up leaves for ranges of 100, 200 or 300 meters. The front sight is a well-protected simple post style, which is adjustable laterally for windage, and horizontally for raising or lowering the point of aim. A special tool is used for adjustment of the front sight.

The cyclic rate of the weapon was designed to be 500 to 600 rounds per minute; often considered ideal for a submachine gun. The Swedish submachine gun was designed for full automatic operation only, although single shots can be accomplished by trigger manipulation. The Swedish K was a well made piece, but it offered no new innovative features. Impressed with the Swedish K, the Egyptian government purchased the manufacturing rights in the 1950s and produced their own version called the Port Said. Most of the parts will interchange with the Swedish model.

The Swedish K M45 model was originally designed for the Suomi M31 50-round “coffin” magazine that was already in service with the Swedish military. The large Suomi magazine was a complex design that featured two separate springs and followers. The magazine was designed and patented by Adolph Schillstrom and was originally called the duplex magazine. The Swedish K could also use the forty and seventy-one round drums of the M31.

In the late 1940s, a new redesigned magazine was introduced to replace the original heavy and difficult to load Suomi duplex magazine. The new magazine was an excellent wedge-shaped double stack, double feed design with a capacity of 36 cartridges. Holes were provided in the rear of the magazine body so that the operator could see how many cartridges remained. A modification to the submachine gun followed, with a removable magazine housing being added. This gave lateral support to the new 36 round magazine, and could be easily removed to permit use of the older Suomi 50-round magazine and drums. Later models were manufactured with a fixed, non-removable magazine housing that could only use the latest 36 round box type magazine. These were designated as the M45/B.

With its stock in the extended position, the Swedish K has an overall length of 31.8 inches. With the stock folded, the length is reduced to 19.8 inches. Weight with a loaded 36-round magazine in place is 9.25 pounds. The fifty round duplex magazine adds 2.6 pounds and a seventy one round drum adds 4.4 pounds to the weapon.

Accessories for the Swedish submachine gun included a unique clip-on night sight, ejection port cover, brass catcher, magazine loader and clips, sub-caliber training and blank ammunition and special barrels. There was also special high-velocity M39 armor-piercing 9mm ammunition issued with the weapon.

Although the Swedish K was in production for nearly twenty-five years and produced in far greater numbers than the Smith and Wesson Model 76, transferable Swedish K submachine guns are uncommon in the United States, and the majority of those that do exist were assembled with “new” manufacture receiver tubes. Original examples are not common except perhaps as dealer samples.

Smith and Wesson Model 76

During the Vietnam conflict, the United States Navy had begun to procure submachine guns for use by its SEAL teams, a special operations force operating in-country. SEAL teams often used foreign submachine guns for covert operations. Unhindered by any political or official standards or requirements for their proposed submachine guns to meet, the SEAL’s weapon of choice was the excellent and highly accurate 9mm Swedish-K submachine gun. Problems with procurement of the Swedish submachine gun were eventually encountered due to Sweden’s outspoken protest of the U.S. involvement in the Vietnam War.

During the early spring of 1966, the Navy Department contacted Smith and Wesson representative, Mr. George Ersham, to inquire about designing and manufacturing a weapon that would be similar in design and operation to the Swedish-K. By the fall of 1966, the Development Section of Smith and Wesson received an official written request from the Department of the Navy for development of a new 9mm submachine gun. By January of 1967, a prototype weapon was completed and ready for testing. The weapon that was designed by the engineers at S&W looked similar to the Swedish submachine gun it was to replace, but there were quite a few differences. After preliminary testing, a small lot of one hundred Smith and Wesson submachine guns were produced for further testing in-house and in the field. In mid-1969, after a few minor design changes were implemented, the weapon went into production as the Smith and Wesson Model 76 9mm Submachine Gun. In addition to the Navy contract, Smith and Wesson planned to offer their new American submachine gun to U.S. law enforcement agencies to replace their aging Reising and Thompson weapons.

The Model 76 is a simple but durable weapon primarily made from heavy sheet metal stampings. The receiver tube was produced from heavy .120-inch thick seamless steel tubing. The inside of the receiver tube was grooved (often called sand cuts) to help prevent stoppages from sand or debris that may collect inside the receiver. The appendages: sights, magazine housing and sling swivels were heliarc-welded to the receiver tube. The fixed sling swivels were intended to employ the common U.S. issue M1 carbine sling. The fixed magazine well is flared at the bottom for quick insertion of a magazine. The eight-inch barrel could be easily removed for cleaning or replacement via a barrel nut, but there is no way to index the barrel onto the receiver. As a result, consistent accuracy suffered. A heavy perforated, tubular shroud was provided to protect the operator’s hands from a hot barrel. The sights are calibrated for a 100 meter range and are nonadjustable (except by bending or filing) and are welded directly onto the receiver tube. The rear sight is mounted at the end of the receiver closer to the shooter’s eye. The front sight is mounted on the front end of the receiver. A more positive safety feature was implemented into the S&W 76 Model.

The M76 is capable of both semiautomatic and full automatic fire, by means of an ambidextrous fire/safety selector lever. The full automatic cyclic rate of fire is 720 rounds per minute, which is somewhat faster than the Swedish K. The trigger of the M76 is very firm requiring up to fifteen pounds of pull to operate. The stiff trigger makes the delivery of accurate semiautomatic fire very difficult and somewhat uncomfortable.

The S&W 76’s folding buttstock is made from flat steel stock that is approximately .140-inches thick. The rear portion of the stock was covered with a thin vinyl material. The buttstock folds and locks to the left side (the Swedish K stock folds to the right) of the receiver as to not interfere with the cocking handle if the weapon was fired with the stock folded. When in the extended position, the stock is not nearly as solid as the Swedish K, and usually will wear – developing lateral play after a short period of time.

The Smith and Wesson 76 was finished in a military style medium gray phosphate, which is non-reflective and quite durable in the field. The one-piece pistol grip is made of a black plastic material. The S&W 76 was designed to be disassembled by the removal of the single screw that retains the grip, utilizing the magazine’s base as a screwdriver. The M76 has an overall length of 20.25 inches with the stock in the folded position. With the stock extended the length is 30.38 inches. The loaded weight with a 36-round magazine is 8.67 pounds.

The thirty-six round magazines designed for the S&W 76 submachine gun, were copied from the Swedish-K weapon. The magazines were of the proven double-stack, double-feed design and very reliable. Original factory magazines can be identified by markings on the floorplate. The magazines are difficult to load to capacity without the aid of a magazine loading tool. The excellent magazine loading tool and stripper clips designed for the Swedish K can be used to load the M76 magazine.

Regular production models have a letter “U” prefix. Production serial numbers ran from U101 to U6100. The serial numbers of the production guns were marked on the right rear side of the receiver tube. The original retail cost of a Model 76 submachine gun in 1969 was $80. The Navy purchased a number of the Model 76 submachine guns and classified them as; Navy Mark 24 Mod 0, NSN 1005-01-013-6050. Although the exact number procured by the Navy is unknown, the total was believed to be limited. Smith and Wesson discontinued manufacture of the Model 76 in July, 1976. This presented problems obtaining spare parts to maintain the weapons. By the late 1980s, the M76 were phased out of the Navy inventory.

Summary

A) Availability. Although the Swedish weapon was made in far greater numbers than the M76, there are relatively few transferable examples available in the U.S., and most have “new” manufacture receiver tubes.

Despite a very short production run, most of the Smith & Wesson submachine guns remained in the U.S., and the majority of them are transferable. The S&W 76 can often be found in excellent to new condition as most examples sold to law enforcement saw little use. The M76 is also on the BATF Curio and Relics list making them available to enthusiasts in “C&R machine gun only” states.

Advantage: Smith & Wesson M76.

B) Basic Construction. The Swedish K is a simple weapon made almost entirely of thin sheet steel. The housing for the trigger and sear assembly is held together with rivets and not readily accessible. Some repairs or parts replacement may require a qualified gunsmith.

The M76 has an extremely thick receiver tube that is virtually indestructible. The welds used throughout the weapon, though visible, are of excellent quality. The housing that contains the trigger, selector and sear is easily removed and parts replacement can be performed in the field. The S&W 76 is slightly smaller in size and lighter than the Swedish K, and feels “handier.”

Advantage: The S&W Model 76.

C) Mode of Fire. The Swedish K is only capable of full-automatic fire, although single shots are possible with trigger manipulation.

The Model 76 has a selector and will fire semiautomatic or full automatic. Advantage: Smith and Wesson Model 76.

D) Cyclic Rate of Fire. The Swedish K’s cyclic rate of fire is approximately 550 to 600 rounds per minute, making the weapon easy to control.

The M76 fires noticeably faster than the Swedish K at 700 to 750 rounds per minute, which is too fast for good controllability from a weapon of this type. Advantage: Swedish K.

E) Accuracy. The slower cyclic rate of the Swedish K, along with its sturdy folding stock, makes the weapon very accurate. The indexed barrel aids in better accuracy to a limited degree.

The M76 stock is too flimsy and it fires too quickly for good accuracy. The barrel is not indexed which is a disadvantage. Although the M76 has a semiautomatic capability, the trigger pull is very stiff limiting accuracy in that mode of fire. Advantage: the Swedish K.

F) Sights. The Swedish K. The well-protected post-style front sight of this weapon is adjustable for windage or vertically by rotating it. A tool is required for adjustment. The rear notch style sight is also well protected and has three flip up leaves for 100, 200 or 300 meter ranges.

The Model 76 has only rudimentary sights that are fixed in place by welding; the only adjustment is by bending or filing. The rear sight is an aperture style. Advantage: The Swedish K. G) Parts Availability. Although the availability of spare parts for the Swedish K seems to diminish more each year, parts are still available. In some cases, new parts can still be located. Surplus parts are usually reasonably priced. There are virtually no factory spare parts for the Model 76. Since most are transferable, there are no parts sets available. There are a few individuals making some high-use spare parts for the weapon, but they are expensive due to today’s higher cost of manufacture. Advantage: The Swedish K.

H) Magazines. The Swedish K, with the removable magazine well, can use a wide variety of magazines. All are very inexpensive and currently are readily available. The Suomi 36-round magazines are especially inexpensive and can still be found in new condition. The fifty round coffin magazines are also easy to find. Possibly the most popular magazines are the seventy-one round drums, still widely available and extraordinarily cheap.

Original Smith and Wesson M76 factory magazines can be difficult to find and are expensive. Fortunately the inexpensive M31 Suomi magazines are easily adapted to work in the M76. Only box type thirty-six round magazines will fit in the M76. Advantage: The Swedish K.

I) Accessories. Accessories often make a weapon popular. Everyone likes to collect all of the various items that were made for their guns.

The Swedish K had a number of accouterments, most of which are described in the text of this article. One of the handiest items is the Swedish magazine loader and accompanying steel loading clips. This loader makes loading magazine possible in just seconds. Also popular is the Swedish training ammo that is very inexpensive and, as a bonus, comes on the steel loading clips! Although a special 5mm barrel is required, several individuals are currently manufacturing them.

There are virtually no accessories or accouterments available for the S&W M76. The submachine gun was designed to use the M1 carbine sling. A few items from the Swedish K can be used, particularly the magazine loader and clips. Newly made 5mm barrels to utilize the Swedish training ammunition are currently being manufactured for the Model 76 by several individuals. Advantage: The Swedish K.

Conclusion

The Swedish K is a very accurate submachine gun. The inexpensive seventy-one round drum and thirty-six round magazines further enhances its desirability. However as mentioned, a transferable example can be hard to locate.

The Model 76 is an alternative to a Swedish K. They currently are fairly easy to find, less expensive and are listed as Curio and Relics. Although original magazines are expensive, the cheap Suomi magazines can be easily adapted to fit.