This item is not included in any spawn asset, but it doesn't necessarily mean that it doesn't spawn naturally on any of the maps.
PistolDualHP.dat
GUID 5ec0ee024b864947a765dfef3e0001e7
Type Magazine
Rarity Epic
ID 52569
Size_X 1
Size_Y 1
Size_Z 0.1
Amount 16
Count_Min 16
Count_Max 16
Firerate -2
Ballistic_Damage_Multiplier 1.1
Recoil_X 1.1
Recoil_Y 1.1
Calibers 1
Caliber_0 51338
Tracer 51000
Blueprints 1
Blueprint_0_Type Ammo
Blueprint_0_Supplies 1
Blueprint_0_Supply_0_ID 52569
Blueprint_0_Build 30