This Ammo Grab Bag is without a doubt the very best of it's type.
It's very well made with lots of extra pockets that can accommodate a variety of different items. It's just enough bag, not too much, not too little.
It's perfect for carrying a enough ammo to go into a battle, for one primary rifle such as an AR15 styled rifle. With its three mag pouches on the front able to accommodate 6 AR15 type 30 round sized magazines, and the smaller pouches can hold enough 10 round stripper clips of the 5.56mm ammo to completely reload all 6 mags of 180 rounds. While still leaving the main compartment open for a side arm, more ammo, other supplies & equipment or just to use as a dump pouch. I've not yet tried to set one of these bags up for use with an 7.62NATO Rifle such as an M1A, HK91, or FAL styled rifles. However I'm confident that it would work out very well. The shoulder strap has a huge available adjustment so that even the largest build and most robust of men can adjust it for comfortable carry.

All in all I'd say the British Army got this one right to a point of perfection.