ACP-131

ACP-131 is the controlling publication for the listing of Q codes and Z codes. It is published by the Combined Communications Electronics Board (CCEB) countries (Australia, New Zealand, Canada, United Kingdom and United States), and revised from time to time. When the meanings of the codes contained in ACP-131 are translated into various languages, the codes provide a means of communicating between ships of various nations, such as during a NATO exercise, when a common language is not in effect.

History

The original edition of ACP-131 was published by the U.S. military during the early years of radio telegraphy for use by radio operators using Morse Code on continuous wave (CW) telegraphy. It became especially useful, and even essential, to wireless radio operators on both military and civilian ships at sea before the development of advanced single-sideband telephony in the 1960s.

Reason for the codes

Radio communications, prior to the advent of landlines and satellites as communication paths and relays, was always subject to unpredictable fade outs caused by weather conditions, amount of emission power in kilowatts at the transmitter, radio frequency of the transmission, type of emission, type of transmitting antenna, signal basewave shape and size, sensitivity of the receiver and presence, or lack of presence, of atmospheric reflective layers above the earth, such as the E-layer and F-layers, the type of receiving antenna, the time of day, and numerous other factors.

ACP

ACP may refer to:

Organizations

Science & technology

.25 ACP

The .25 ACP (Automatic Colt Pistol) (6.35×16mmSR) is a semi-rimmed, straight-walled centerfire pistol cartridge introduced by John Browning in 1905 alongside the Fabrique Nationale M1905 pistol. In more recent years, most pistols available in .25 ACP are also available in a more effective caliber.

Design

The cartridge was designed by John Browning for early blowback pistols that lacked a breech locking mechanism. The cartridge was designed to duplicate the performance of a .22 Long Rifle cartridge, when fired from a 2" barrel. The .25 caliber was the smallest case Browning could use, and utilize primer pocket, and sufficient rim. The greased, coated lead bullet design, standard for the .22 long rifle of the day, was replaced with a copper jacketed round nose profile for more reliable feeding in auto loading pistols. The bullet weight was typically 50 grains, keeping with the sectional density of the 40 grain .22 caliber bullet. The cartridge is of semi-rimmed design meaning that the rim protrudes slightly beyond the diameter of the base of the cartridge so the cartridge can headspace on the rim. A recessed extractor groove allows an extractor to grab the cartridge reliably. It is the smallest centerfire pistol round in production, and is commonly chambered in small, so-called "vest pocket" pistols. The .25 ACP achieved widespread use after Colt introduced the Browning-designed Fabrique 1905 vest pocket (sometimes referred to as 1906) to the United States as the Colt Model 1908 Vest Pocket.

.32 ACP

.32 ACP (Automatic Colt Pistol), also known as the .32 Automatic is a centerfire pistol cartridge. It is a semi-rimmed, straight-walled cartridge developed by firearms designer John Browning, initially for use in the FN M1900 semi-automatic pistol. It was introduced in 1899 by Fabrique Nationale, and is also known as the 7.65×17mm Browning SR or 7.65 mm Browning.

History

John Browning engineered a number of modern semi-automatic pistol mechanisms and cartridges. As his first pistol cartridge, the .32 ACP needed a straight wall for reliable blowback operation as well as a small rim for reliable feeding from a box magazine. The cartridge headspaces on the rim. The cartridge was a success and was adopted by dozens of countries and countless governmental agencies.

When the .32 ACP cartridge was introduced, it was chambered in a variety of popular blowback automatic pistols of the day, including the Colt Model 1903 Pocket Hammerless, the Savage Model 1907 Automatic Pistol, and the Browning Model 1910 Automatic Pistol. To avoid patent infringement John Pedersen designed the Remington Model 51 so as to not to rely on any other, thus the unique hesitation lock breech mechanism was developed. The .32 ACP has been chambered in more handguns than any other cartridge. Between 1899 and 1909, Fabrique Nationale produced 500,000 guns chambered for .32 ACP.