This research talks about weapon collections, more preciely, about the ways of presenting them to visitors and the forms of protection and extension of their lifespan. At the beginning there are stated the legal rules of the Republic of Croatia regarding keeping a collection of weapons, i.e. old weapons. There is focus on the categorization of weapons according to the required permits for possession and the term "old weapon" is defined. Then the rules for keeping old weapons prescribed by laws in Slovenia, the Czech Republic, Australia and some Nordic countries are also analyzed. In the following, it is talked about weapons as composite objects because they consist of several different materials, the materials that can most often be found on weapons, their features and reactions to various conditions and ways of protecting them are listed. Then the necessary interventions before and during the conservation process are clarified, and there are described the procedures for deactivating explosive objects to make them safe for storage in the collection. Furthermore, the history of keeping weapon collections is explained, the current types of weapon display are listed and clarified, and the work of war museums is explained, followed by descriptions of the American Firearms Museum Cody, the Swiss Museum of the Old Armory in Solothurn, and also the Croatian History Museum.