Personal defense weapons (PDWs) are compactmagazine-fedautomatic firearms, typically performing as asubmachine gun designed for secondary defensive use rather than as a primary service weapon. Some PDWs fire a small-caliber (generally less than 8 mm or 0.31 in inbullet diameter), high-velocitycenterfirebottleneck cartridge resembling a scaled-downintermediate cartridge, essentially making them an "in-between" hybrid between a submachine gun and a conventionalcarbine assault rifle.
The name describes the weapon's original conceptual role: as a compact but powerfulsmall arm that can be conveniently carried for personal defense, usually by support personnel behind the front line such asmilitary engineers,logistic drivers,medical specialists,artillery crews, orsignallers. These "second-line" personnel are not strictly combat troops expected to directly engage the enemy, but may still be at risk of encountering decently equipped (and often well-armored) hostileskirmishers andinfiltrators, therefore having to defend themselves inclose quarters. Such encounters were thought to warrant an effective weapon that would have sufficient range for engagements that exceed handgun capabilities, but without the unnecessary bulk of a full-sizedservice rifle causing a burden during their normal duties. However, the concept has generally proven unsuccessful for this application, with carbines still being widely preferred for these roles.
In the late 19th and early 20th centuries, shortened versions of the infantry rifle were issued as "carbines" for cavalry troops and gun crews. This designation was dropped as infantry rifle designs became shortened overall, such as in theShort Magazine Lee–Enfield rifle. Thereafter,handguns were typically issued as self-defense weapons. However, they were not effective in mostclose combat situations.[citation needed] As a result, during the First World War, theMauser C96 and artillery versions of theLuger pistol were issued with attachable shoulder stock holsters, which allowed for greater control and accuracy.
During World War I, the United States secretly developed thePedersen device attachment for theM1903 Springfield rifle that allowed it to fire the.30-18 Auto (7.65×20mm Longue) pistol cartridge insemi-automatic mode.[1][2] This attachment was developed to allow an infantryman to convert "his rifle to a form of submachine gun or automatic rifle" in approximately 15 seconds.[2][1]
Production of the device and modified M1903 rifles started in 1918.[2] However, the war ended before they were sent to Europe.[1][2] The contract was cancelled on March 1, 1919, after production of 65,000 devices, 1.6 million magazines, 65 million cartridges and 101,775 modified Springfield rifles.[1][2][3] The Pedersen device was declared surplus in 1931.[3] To prevent them from falling into the hands of the lawless, nearly all of the stored devices were destroyed by the Army except for a few examples kept byOrdnance Department.[4][3]
In 1918, Ribeyrolles, Sutter and Chauchat designed theChauchat-Ribeyrolles 1918 submachine gun. This weapon was meant to be used for close-range protection for the French tank crews. The weapon is based on the RSC Mle. 1917 semi-automatic rifle mechanism. The first trials used a Mannlicher–Berthier clip holding eight cartridges. The trials continued until 1919 with a weapon using the same magazine as the Chauchat. The results were satisfactory but the weapon was too powerful for the intended self-protection use. A mix of standard and tracer bullets was planned to be used to assist in aiming.
In 1938, the U.S. Army Ordnance Department received a request for a light rifle to be issued to mortarmen, radiomen, drivers, clerks, cooks, and similar grades.[5] During field exercises, these troops found that theM1 Garand rifle was too heavy and too cumbersome for general issue.[citation needed] And, while handguns are undeniably convenient, they had limited range, accuracy and power.[citation needed] This request was refused by authorities.[5]
In 1940, after Germany's use of glider-borne and paratroop forces to infiltrate and attack strategic points behind the front lines,[6][7] the request for a light rifle was resubmitted and subsequently approved.[5] U.S. Army Ordnance issued a requirement for a "light rifle" with greater range, firepower, and accuracy than theM1911 pistol while weighing half as much as the M1 Garand.[8] As a result, the U.S. developed the semi-automaticM1 Carbine and shortly thereafter the select-fire M2 Carbine.
In 1969,AO-46 was an unsolicited design byPeter Andreevich Tkachev working atTsNIITochMash. Although not accepted for service, this design, in combination with report of the US use of theXM-177 in Vietnam led theGRAU to start the competition known asProject Modern, which led to the adoption ofAKS-74U for service.[9][10]
Introduced in 1991, theFN P90 features abullpup design with a futuristic appearance. It has a 50-round magazine housed horizontally above the barrel, an integratedreflex sight and fully ambidextrous controls.[11] A simple blow-back automatic weapon, it was designed to fire theFN 5.7×28mm cartridge which can penetrate soft body armor.[12][13] The P90 was designed to have a length no greater than a man's shoulder width, to allow it to be easily carried and maneuvered in tight spaces, such as the inside of an armored vehicle.[11]
Introduced in 2001, theHeckler & Koch MP7 is a direct rival to the FN P90. Featuring a more conventional-looking design, the MP7 uses a short-stroke piston gas system as used on H&K'sG36 andHK416 assault rifles, in place of ablowback system traditionally seen on submachine guns.[14] The MP7 is able to use 20-, 30- and 40-round magazines and fires4.6×30mm ammunition which can penetrate soft body armor. Due to the heavy use of polymers in its construction, the MP7 is much lighter than older SMG designs, weighing only 1.9 kg (4.19 lb) with an empty 20-round magazine.
The PDW concept has not been widely successful, partly because existing PDWs are not significantly cheaper to manufacture than carbines or full-size military rifles. Most PDWs also use a proprietary cartridge, such as the 5.7×28mm cartridge for the FN P90 or the 4.6×30mm for the H&K MP7, neither of which were originally compatible with any existing pistols or rifles/carbines. Although both manufacturers planned handguns that used the same proprietary rounds, only FN went forward with production of the Five-SeveN pistol, which was the only handgun option available for the 5.7×28mm cartridge for over two decades until the introduction ofRuger-57 in 2019. In turn, this made the PDW cartridges expensive to consumers due to the lack of mass production.[15]
Though personal defense weapons have not been very popular for their intended application, they have been acquired by various militaryspecial forces units andlaw enforcement groups, as an upgrade for their older submachine guns[citation needed]. The FN P90 and Five-seven pistol are used by military and police forces in over 40 countries, including Canada, Cyprus, France, Greece, India, Peru, Poland, Spain, and the United States.[16] The Heckler & Koch MP7 is also used in a number of countries, including Austria, France, Germany, Ireland, Norway, Malaysia, and the United Kingdom.[17][18]
| Name | Cartridge | Country | Serial production |
|---|---|---|---|
| Brügger & Thomet APC9 RWS ACTION SE Gen. II SXF variant | 9×19mm, regular loads and armor piercing RWS ACTION SE Gen. II SXF loads | Switzerland | |
| Brügger & Thomet MP9 | 6.5×25mm CBJ,9×19mm | Switzerland | yes |
| Colt SCAMP | .22 SCAMP | United States | no |
| ČZW-438 | 4.38×30mm Libra | Czech Republic | no |
| FN P90 | 5.7×28mm | Belgium | yes |
| Heckler & Koch MP7 | 4.6×30mm | Germany | yes |
| Saab Bofors Dynamics CBJ-MS | 6.5×25mm CBJ | Sweden | no |
| SR-2 Veresk | 9×21mm Gyurza | Russia | yes |
| ST Kinetics CPW | 4.6×30mm,5.7×28mm,9×19mm[22] | Singapore | yes |
| Tuma MTE 224 VA | .224 Voboril | Switzerland | no |
| VBR-Belgium PDW[15] | 7.92×24mm | Belgium |
| Name | Cartridge | Country | Serial production | Note |
|---|---|---|---|---|
| AAC Honey Badger | .300 AAC Blackout (7.62×35mm) | United States | yes | |
| AKS-74U | 5.45×39mm | Soviet Union | yes | |
| AO-46 | 5.45×39mm | Soviet Union | no | |
| AR-57 | 5.7×28mm | United States | yes | M16 lower receiver with a redesigned upper receiver fed by FN P90 magazines |
| Barrett REC7 PDW | 6.8mm Remington SPC (6.8×43mm) | United States | ||
| Floro PDW | 5.56×45mm | Philippines | ||
| FN SCAR PDW | 5.56×45mm | Belgium | yes | |
| GA Personal Defense Weapon | 7.62×37mm Musang | Philippines | ||
| GAU-5A Aircrew Self Defense Weapon | 5.56×45mm | United States | yes | Takedown gun |
| Globserver PDW[23] | 9x19mm Parabellum | Hungary | yes | |
| Heckler & Koch MP5K-PDW | 9×19mm Parabellum | Germany | yes | |
| Knight's Armament Company PDW | 6×35mm KAC,.300 Blackout | United States | yes | |
| Magpul PDR | 5.56×45mm | United States | no | |
| SAI SMG Tiger Cub[24] | 9x19mm Parabellum | Denmark | yes | |
| SIG MCX Rattler | 5.56×45mm,.300 Blackout | United States | yes |
