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_Nailgun_Mag.dat
GUID 750d522bb8314ae9848100fd5d9e7c27
Type Magazine
Rarity Rare
ID 59955
Size_X 1
Size_Y 2
Size_Z 0.3
Amount 30
Count_Min 11
Count_Max 30
Calibers 1
Caliber_0 59955
Tracer 59067
Blueprints 3
Blueprint_0_Type Tool
Blueprint_0_Searchable False
Blueprint_0_Supplies 1
Blueprint_0_Supply_0_ID 58999
Blueprint_0_Supply_0_Amount 1
Blueprint_0_Tool 58999
Blueprint_0_Tool_Critical
Blueprint_0_Build 27
Blueprint_1_Type Ammo
Blueprint_1_Supplies 1
Blueprint_1_Supply_0_ID 59955
Blueprint_1_Build 30
Blueprint_2_Type Gear
Blueprint_2_Supplies 1
Blueprint_2_Supply_0_ID 59241
Blueprint_2_Supply_0_Amount 1
Blueprint_2_Supply_0_Critical
Blueprint_2_Build 30
Delete_Empty