M9 is the official
United States Armed Forces designation of the
Beretta 92F pistol which they adopted in
1985 to replace the legendary
m1911 pistol in
.45 ACP.
Beretta won the contract because although
SIG was able to produce a pistol that met the requirements and sell it for a slightly lower price,
Beretta was able to have a better
bid for the price of
spare parts.
The choice of 9mmx19 in this new sidearm was mostly logistical as that was the standard NATO pistol round, it continues to be so to this day.
Read more about this wonderful handgun here.