The Colt BOA was only made in limited numbers for a single year, then sold through a single distributor, making it probably the most elusive and desirable of the company’s double-action revolvers.
Between 1950 and 2003, Colt delivered to wheel gun aficionados a series of seven now-classic “snake” guns: Cobra, Python, Diamondback, Viper, BOA, King Cobra, and Anaconda. Some of these were more popular and widespread, such as the Diamondback which was made in both .22LR and .38 Special, while some were less frequently encountered, such as the Anaconda which was made in .44 Mag and .45 Colt. For seekers of the seven serpents, however, a couple of these guns are almost impossible to find: the Viper, which was just a regular catalog item for Colt in 1977, and the BOA, which is even rarer.
In fact, for many Colt fans, it is kind of a holy grail.
More in my column at Guns.com, where I checked out BOA #513.