First of all Duty gun means something different for Military and Police, but both come always with ammunition use.
A Police gun will shoot manstopping ammo that won't cut through the body to not endanger others around also causing less harm to the body by beings still leathel when needed.
Military guns shoot to kill and need to have high penetration and harm capabilities.
Therefore, the ammunition design is as important as the gun itself. Does the ammo stretch out in the body to ripp more human tissue apart, is it penetrating body armour and will cut through several rows of enemies or will the ammo stop in the human body causing harm disabling movement while causing little chance of innocent bystanders being harmed.
For Police guns the carry storage is more important than for military purposes and that turns the holster fitting into the Police car as important as the ammo, while military needs to consider the weight of gun and ammo designing supply lines from basically the factory to a battleground in far distance with storage and transportation.
Ammunitioning is no regularly used term for Police, while seat belt is no major concern for military personnel.
Old does not mean bad. It well can mean technological perfection.
A 1911 is a very old design. It is reliable and known. Varieties come by using different materials from aluminium to polymeres. They all will have in common a long barrel ensuring precision, heavy impact ammo use capabilities and a flat design taking little space in storage.
A Glock is offering high magazine capability and simple handling.
Which gun used, depends on the mission and only on the mission.
As a gun manufacturer offering a duty gun you have to understand first your production capabilities based on which design you are able to produce as close to technical perfection as possible. That would be 0.1 percent failure during post-production pre-delivery quality control final checks which is even another stand point.
#MIB
PS: That's why blunt corruption is so bad. The industrial military complex straight forward kills by corruption, but the very own guys.
