Gunner wrote:

Actually..an arsenal is a place where weapons are manufactured. An
armory is where they are stored.

arsenal 1. A governmental establishment for the storing,
manufacturing, or repairing of arms, ammunition, and other war
materiel. 2. A source of supply for arms and other munitions. 3. A
stock of weapons.

armory 1. A storehouse for arms; an arsenal. 2. A building for
storing arms and military equipment, especially one serving as
headquarters for military reserve personnel. 3. An arms factory.

- American Heritage Dictionary, New College Edition, 1976