Michael (if I may so),
The lighting conditions of the actual exhibition layout of the Real Armería in Madrid (RAM) are not exactly ideal for photographing. It's allowed, yes, but not with tripods, and flash is absolutely forbidden. This makes things somewhat difficult when trying to get decent pictures...
The sad part is that the RAM has a very small amount of publications regarding their collection, although the extremely few they put out are of very high quality. I'm sure I don't have to point you, although it deals with a much later time period than the one you focus on, to the last work by Álvaro Soler Del Campo, RAM's curator, published in occasion of last year's exhibition on their collection of "arquebuses" from Madrid's workshops. The reference for the book is:
SOLER DEL CAMPO, Álvaro (2006), "Catálogo de arcabucería madrileña (1687-1833) Real Armería de Madrid", Ed. Patrimonio Nacional, Madrid.
Hardback, Folio, 409 pp.
The exhibition was fantastic, the actual pieces in the RAM are outstanding, and the catalog is extremely good, both from the artistic and the academic point of view. It's in Spanish, though, I have to say.