The transfer follows approval of the sale by Spain's Ministry of Defense, which owns the land and certain assets of the facility.
Under the acquisition deal, Nammo will retain the existing workforce at the facility in Palencia as well as its current manufacturing activities.
The factory manufactures military ammunition.
Nammo's intent to acquire the facility was first announced late last year but the deal was delayed. The Spanish Ministry of Defense required additional time to look at other possible buyers of the operation.
The Palencia plant was originally a state-run enterprise and was sold to General Dynamics European Land Systems in 2001.
Transaction details were not immediately available.
Nammo develops and produces military and sports ammunition, shoulder-fired weapon systems and rocket motors.
General Dynamics European Land Systems Santa Barbara Sistemas, with six factories in Spain, is the main supplier of combat vehicles and artillery systems for the Spanish Army.
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