Military experience does count as long as the work is relevant. A good understanding of both the licence requirements and the ATA CHAPTER SYSTEM. Then work carried out can be logged. ie tasks on navigation systems could count, but weapons systems no. However fixing a broken cable in a weapons system could count as the task is to fix a broken wire.
Therefore it is possible to gain a licence whilst still serving in the military. The problem would is that this licence would be frozen and you could not certify until you have worked for a part 145 company for a year. This may seem odd but also remember that you need to have done a type course and completed a certain amount of experience on that type before you can certify.
So if you joined a company with a basic B2 licence, the chances are you would have worked at that company for more than a year before you have completed the type course and associated work experience to use your licence.