I asked the same question about the BC difference berween the JLK's and the Bergers. Bryan Litz answered the thread and was very helpful.
Bryan recently compiled a lot of balaistic data for a lot of bullets and published a book on it. He came up with G1 and G7 BC's for these bullets and the data was imported into the JBM ballistics calc. If you you use the bullet drop down and select a particular bullet, any bullet followed by Bryan's name "Litz" will use that BC info to calculate all the downrange data. I did a comaprison between the the 180 Berger 7mm and the 180 JLK 7mm and then I took the velocity of both bullets at 1000 yds and plugged it into the BC clac program and found the tow BC's to be very close with the Berger having a slight advantage. There is really no way that with the similar shapes and lengths of the Bergers and the JLK's that their BC's could differ by much.