As far as I know (and some one can correct me here if I am wrong) PMC is Military grade brass, and as a result the crimp all their primers in place.
I have used some, and its good brass but it is a little more work. If you are determined to use it, you need good strong decaping dies (again mine are RCBS), a strong press (I use an old school RockChuker) and having a spare decaping pin on hand is a good idea as well.
There is also a die set that is used to remove the crimp in the primer pockets (mine is RCBS).
If you plan to re-use a lot of mil-bras, it would be a good idea to get these tools, otherwise you may be better off just sticking with commercial brass like winchester.
One note on using mil-brass. It is generally heavier than comercial brass, and as a result the preaseures are higher. If your going to use it to reload, its a good idea to reduce your starting point more (ie 10% instead of the normal 5%) as long as that starting point is above the minimum load in your puplished reloading manual specs. Over light loads have their own associate dangers and you should consult your reloading manual.
Hope this helps, and remeber, this is free advice and worth what you paid for it
regards
AbH