Hi,
If you've got a broken part, it's a huge disadvantage.
The follower spring in the magazine could be weak or broken.
Describe the markings on your Luger and we may be able to help you identify it. Pictures tell much more...
Use Google to search for "luger disassembly" and you'll find quite a bit of information that will help you. Our own site has the information here:
http://lugerforum.com/disassembly-1.html
No, the hold open spring (attached to the hold open inside the action) is different from the magazine catch spring (which is on the button you press to drop the magazine).
I was referring to part number "022" in this diagram:
http://lugerforum.com/lugerparts.html
If you're really unsure about working with your Luger, best to take it to a gunsmith familiar with them.
Marc
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Igitur si vis pacem, para bellum -
- Therefore if you want peace, prepare for war.