You should also check firing pin protrusion... if the pin is not matched to the breechblock, it may be too short or fall outside of the acceptable tolerances...
Here is an extract from the original Luger Blueprint for the Firing Pin. If you, or anyone else would like a full copy of the blueprints (which are a fascinating study in themselves) to check measurements on your Luger, you can order the CD in the For Sale forum. (Yes! another shameless plug for the Blueprint CD!
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