David,
See Jan Still's website:
http://luger.gunboards.com/. Takedown is easy. See the Marstar website for a diagram. The Steyr Hahn is my favorite WWI pistol after the Luger. Simple and super accurate. The only problem is the extremely heavy trigger pull that can't be modified and the scarcity of ammo. I was lucky to buy a cache of 1935 RWS ammo that will last me a lifetime. Be advised that this gun was NOT designed to fire 9mm Largo. The 9mm Steyr cartridge is unique. Fiocchi makes it but it is expensive. Enjoy. KFS