If you want your rifle mags close and your rig slim, the Emerson Gear double elastic magazine pouch is a sensible choice. It carries two M4/AR style magazines in a low-profile pouch that sits close to your kit.
The elasticated body moulds around the magazines and holds them firmly until you need them, then a simple pull releases them. It attaches to any MOLLE system, so it works on chest rigs, plate carriers and belts alike.
