Any advantage to the .223 mag?

In the custom weapon menu, some weapon can get their magazine replaced by a .223 x 20 magazine. On some weapon (SVD...) it allow to have far more ammo than their base caliber, but it also appear on some assault rifle (G44), where it would make you get less ammunition.

Is there any advantage, in accuracy, damage or whatever, to use .223 caliber on a weapon like the G44?