On some 2 is a little tight. How did the real military carry?

IIRC- They are designed to carry TWO per pocket with the bullet tips facing opposite directions. Being nice and snug (tight) keeps the rounds loaded on the clips.

I have one of those cheap Chinese surplus with the ten pouches and the wooden dowel flap closures, I believe that is what you are talking about.  They are designed for 2 clips per pouch for 200 rounds total, although one of the pouches is larger and can hold either a cleaning kit or supposedly up to 40 loose rounds.  I just keep 2 clips per pouch with the rounds alternating directions to fit better.  It is a bit snug but they all fit relatively securely.  Now if I could just figure out how to not lose a round or two every time I pull out a clip (I usually am loading 8 or 9 round clips cause one falls out in the pouch...)

I put two clips per pocket in mine. Bullets opposite one another as another poster said. They loosen up with use. Last winter I practiced loading the rifle from that chest rig with gloves and coat. Took a little effort but by the end I got pretty good at it.