Rational of carrying a backup piece

The backup gun is a second handgun, normally carried concealed, used as a supplement to a primary handgun that may be carried openly or concealed, depending on the circumstances. It has a long history among lawfully armed men and women. Originally a law enforcement practice, the carrying of backup has spread to ordinary American men and women who are licensed to carry loaded handguns concealed in public.
One only has to cruise the “gun boards” on the Internet to notice how many private citizens who carry are either considering the wear of a second weapon routinely, or are already committed to the practice. It has been said that in America, private citizens model their sporting rifle purchases based on what the military is using, and their defensive handgun purchases on what their police are using.
The rise of the bolt-action rifle in popularity among hunters and target shooters followed the adoption of the Krag-Jorgensen in the late 19th century and the Springfield in the early 20th…semiautomatic hunting rifles such as the Remington Model 742 and Winchester Model 100 became popular among a generation of Americans who returned from fighting WWII and the Korean conflict with semiautomatic Garands…and today, the single most popular model represented in new rifle sales seems to be the AR-15, the semiautomatic version of the M-16 that has been our nation’s primary military rifle since the Vietnam conflict..
Similarly, the dominance of the revolver among private citizens followed the adoption by the Texas Rangers of the Walker Colt before the middle of the 19th century. For most of the 20th century, the double-action revolver in 38 Special, followed in popularity by the same type of gun in 357 Magnum, was virtually the standard law enforcement weapon and the most popular home defense/concealed carry firearm among “civilians.”
As the police went to semiautomatics, so did the law-abiding public. At this writing, the high tech auto pistol typified by the Glock is the most common type of police duty handgun, and likewise one of the biggest sellers in the commercial handgun market.

Sometimes it’s easier, and even more efficient, to carry two small handguns of adequate power instead of one large one. Left: 20 ounce Model 640-1 above, 15 ounce Model 442 below, both J-frame 5-shots by Smith & Wesson. Right: 22 ounce all steel Kahr MK9 above, 14 ounce polymer frame MK9 below, both 7-shot 9mms.

This being the case, it is not surprising that the law officers’ taste for a second handgun carried on the person, has been acquired by the armed citizens of the same population.

The Rationale of Backup

There are several good reasons to carry a second handgun for defensive purposes. None are the exclusive province of law enforcement. Let’s examine them in detail.
The primary gun may be taken away. In Kentucky, an armed criminal caught a uniformed policeman off guard and took away his Smith & Wesson 10mm service pistol. The lawman was able to access his concealed Walther PPK 380, a backup gun issued to him by his department, and empty it into his attacker. The criminal died; the officer lived


The primary gun may be unusable because it is the object of a struggle. In Ohio not long ago, a police officer found himself in a desperate battle for survival as his opponent struggled to take away his department issue Glock 22 pistol. Fortunately, the department had had the foresight to issue every officer a Glock 27, a subcompact version of the duty pistol, as backup. In the last instant before the suspect gained control of his service weapon, the officer was able to draw his backup G27 and fire a shot into his would-be murderer’s head, killing the assailant and saving his own life.
The primary gun may be empty. Drawing a second, loaded weapon is often faster than reloading the first when it runs dry. In Michigan, a woman and her husband were working in the store they owned and operated together when they were hit by multiple armed robbers.
The felons shot and wounded the husband early in the encounter. The wife drew a double-action revolver and shot back. Her gun ran dry, and she grabbed a second revolver with which she continued to return fire. That sustained fire allowed her to win the gunfight, saving her life and that of her husband, who survived his wounds. Their attackers were not so lucky.

   I got this from Gun Digest