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.
RevolverDual.dat
GUID 8e5fcb20978548ec9dd03b182ed4ebb1
Type Magazine
Rarity Epic
ID 52566
Size_X 1
Size_Y 1
Size_Z 0.1375
Amount 12
Count_Min 4
Count_Max 10
Calibers 1
Caliber_0 52566
Tracer 51000
Blueprints 9
Blueprint_0_Type Ammo
Blueprint_0_Supplies 1
Blueprint_0_Supply_0_ID 52566
Blueprint_0_Build 30
Blueprint_1_Type Ammo
Blueprint_1_Supplies 1
Blueprint_1_Supply_0_ID 51943
Blueprint_1_Build 30
Blueprint_2_Type Ammo
Blueprint_2_Supplies 1
Blueprint_2_Supply_0_ID 51944
Blueprint_2_Build 30
Blueprint_3_Type Ammo
Blueprint_3_Supplies 1
Blueprint_3_Supply_0_ID 51945
Blueprint_3_Build 30
Blueprint_4_Type Tool
Blueprint_4_Supplies 1
Blueprint_4_Supply_0_ID 51018
Blueprint_4_Supply_0_Amount 1
Blueprint_4_Tool 52560
Blueprint_4_Tool_Critical
Blueprint_4_Product 52566
Blueprint_4_Products 1
Blueprint_4_Build 27
Blueprint_5_Type Tool
Blueprint_5_Supplies 1
Blueprint_5_Supply_0_ID 51018
Blueprint_5_Supply_0_Amount 1
Blueprint_5_Tool 52561
Blueprint_5_Tool_Critical
Blueprint_5_Product 52566
Blueprint_5_Products 1
Blueprint_5_Build 27
Blueprint_6_Type Tool
Blueprint_6_Supplies 1
Blueprint_6_Supply_0_ID 51018
Blueprint_6_Supply_0_Amount 1
Blueprint_6_Tool 52562
Blueprint_6_Tool_Critical
Blueprint_6_Product 52566
Blueprint_6_Products 1
Blueprint_6_Build 27
Blueprint_7_Type Tool
Blueprint_7_Supplies 1
Blueprint_7_Supply_0_ID 51018
Blueprint_7_Supply_0_Amount 1
Blueprint_7_Tool 52563
Blueprint_7_Tool_Critical
Blueprint_7_Product 52566
Blueprint_7_Products 1
Blueprint_7_Build 27
Blueprint_8_Type Tool
Blueprint_8_Supplies 1
Blueprint_8_Supply_0_ID 51018
Blueprint_8_Supply_0_Amount 1
Blueprint_8_Tool 52564
Blueprint_8_Tool_Critical
Blueprint_8_Product 52566
Blueprint_8_Products 1
Blueprint_8_Build 27