Thanks Curl,
I like the earlier ones with the straw best as well.I got lucky with this one as it was a small antique auction and not a lot of gun bidders.I try and buy them when they have condition and all matching with the mag like that when I can.

iqbal,
happy to help but I am no expert.A picture would help greatly but from what you have given for info its a 42 (date ) byf.The serial number will have a suffix which can be tricky to read( my luger pictured is a "f" for instance),here is a link that may help sort it out;
http://www.lugerforum.com/Suffixes/Suffixes.htm

When you disassmble it you should also find that 25 (last two of the 2025) on the trigger and one other place inside.I am not sure if that late,1942 the grips will have the 25 but I would not worry if they didn't.
Here is a link to a forum that is very helpfull with lugers,also Jan Still's books are a must if your going to collect them,they have also been excellent investments.
They are going to want to see a picture as well if you can.

http://luger.gunboards.com/index.php

HTH a bit
Best,
Dave K