The Glock 17 comes with 17 round magazines standard, though many police departments use extended magazines. Some pistols of that era had similar capacities, tho

The Glock 17 comes with 17 round magazines standard, though many police departments use extended magazines. Some pistols of that era had similar capacities, though it wasn't common. The Browning Hi Power came out in 1935 and had a 13 round capacity, and larger magazines (15ish rounds) were available by the 1970s. The Steyr GB was designed in the late 1960s and had an 18 round magazine. Glock's design became popular because it was reliabile, had good capacity, was easy to use, and was inexpensive. Other designs had one or more of those attributes, but not the combination of all of them.