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.
PS_PRO90_Mag.dat
GUID 940da67b98844ef08339badde07554f2
Type Magazine
Rarity Epic
ID 19891
Size_X 2
Size_Y 1
Size_Z 0.12
Amount 50
Count_Min 5
Count_Max 30
Calibers 1
Caliber_0 19891
Tracer 19002
Blueprints 3
Blueprint_0_Type Tool
Blueprint_0_Supplies 1
Blueprint_0_Supply_0_ID 18999
Blueprint_0_Supply_0_Amount 1
Blueprint_0_Tool 18999
Blueprint_0_Tool_Critical
Blueprint_0_Build 27
Blueprint_1_Type Ammo
Blueprint_1_Supplies 1
Blueprint_1_Supply_0_ID 19891
Blueprint_1_Build 30
Blueprint_2_Type Ammo
Blueprint_2_Supplies 1
Blueprint_2_Supply_0_ID 19325
Blueprint_2_Build 30