M231 Submachinegun

300px m231 1 svg

(From http://www.pmulcahy.com/assault_rifles/us_assault_rifles_a-c.htm)

This brings us to a rather weird variant of the M-16 series: the M-231 Port Firing Weapon. (No, that’s not backwards; that’s the proper designation of the weapon.) This version was specifically designed for used from the firing ports of the Bradley series of Infantry Fighting Vehicles.

In its early phases, the M-231 program came down to the Colt version or a version of the Heckler & Koch HK-53, but in the interests of interoperability, the Colt version won out, and became the M-231 PFW. The M-231 has a 14.49-inch heavy barrel (primarily to minimize overheating) tipped with a standard M-16A2 flash suppressor. Just ahead of the short handguard are wide threads which allow the M-231 to be quickly screwed into the Bradley’s firing point swivel ball.

Sighting was meant to be done through primarily through the vision block above the firing ports, with the magazines of the M-231 filled with tracers to allow the shooter to adjust his fire quickly. Feed is from standard M-16 magazines, and internally, the M-231 is for the most part the same as the M-16A2. However, the M-231 fires from an open bolt and the cyclic rate was greatly increased up to 1100-1200 rpm, to provide better suppressive fire. The right side of the M-231 has integral attachment points for a canvas brass catcher. The design of this bag also allowed the fumes from firing the M-231 to be vented outside of the Bradley.

Though the infantrymen inside the Bradley also have M-16A2s or M-4s to grab when they exit the vehicle, the M-231’s could be quickly dismounted and used as conventional short assault rifles if necessary. The M-231 has no iron sights; the trough of the carrying handle is to be used as an emergency short-range sight when the M-231 is dismounted. Early versions of the M-231 were issued with a sliding wire stock for use if dismounted, and even a stock which clipped onto the buffer tube was experimentally tried. The wire stock (or a stock of any kind) was later discarded as being unnecessary, especially after the side firing ports of the Bradleys were plated over in the interests of adding more side armor.

During the Hotwar however, the M-231 had even wider use than was intended by the designers; they were often stripped from immobilized Bradleys and used as submachineguns and PDWs by both military and civilian forces, often with the addition of stocks removed from non-functional M-16s, M-177s, CAR-15s, or M-4s; M-231s were also seen with homemade wooden stocks or sliding wire stocks.

Designation Ammunition Load Magazines Barter
M-231 (With Stock) 5.56mm NATO 3.9 kg 20, 30 $569
M-231 (No Stock) 5.56mm NATO 3.63 kg 20, 30 $544
Weapon ROF Damage Pen Bulk SS Burst Range
M-231 (With Stock) 10 3 1-Nil 4/5 2 10 34
M-231 (No Stock) 10 3 1-Nil 4 2 12 28

M231 Submachinegun

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