As shipped the McMillan stocks do not have pillars installed. If they have been installed you would see an aluminum or steel circle at the outside or inside view of each stock bolt hole. They are usually custom fitted and glued in place by a smith when the stock is bedded. McMillan does not place a full length aluminum bedding block into their stocks, not feasable with their production process from the info I got from a guy who spent a lot of time in their factory.
Pillar bedding might seem reduntant if the receiver is full-bedded but it is a standard in the bedding done by most tactical and long range rifle builders.
Good luck with your build, the A5 is a great long range stock.