The poor range and stopping power of the M-4 rifle (a short barrel M-16) has led to some lively debate over how the infantry squad should be organized. With the XM-29 weapon (the 15 pound 20mm gun firing "smart shells") about to enter use in combat units, there is concern over what mix of weapons is most useful in a squad of nine troops. Normally, the squad is divided into two four man fire teams, each having a 5.56 mm light machine-gun and one soldier with the 40mm grenade launching attachment on his M-16 rifle. Many armies have one machine-gun per squad, plus one soldier with a larger (7.62mm) caliber sniper rifle. The U.S. still has 7.62mm sniper rifles, but these are used by sniper teams controlled by the company or battalion commander. Adding another weapon to the infantry squad is dicey because, as a practical matter, squads in combat quickly lose a third or half their men to combat or non-combat injuries. Vast experience during World War II demonstrated pretty convincingly that the light machine-gun was the key weapon in the infantry squad. The development of lighter machine-guns (those firing the lighter 5.56mm bullets) in the 1960s reemphasized this. The experience in Afghanistan was unique, as most areas where infantry are going to be fighting will be rather more crowded (built up areas, forests, jungles). So why add a longer range weapon to the squad just to deal with unique situations like Afghanistan? But there's still the problem with the XM-29. It currently weighs 18 pounds and the next version is supposed to get it down to fifteen pounds. How many per squad? Will the XM-29 replace any existing weapon? It's all theoretical until the XM-29 gets into battle and one can see how the XM-29 works with light machine-guns and the 40mm grenade launcher. The XM-29 has a max range of 1,000 meters, so it certainly would have been handy in Afghanistan. Or maybe not. You don't know until you try out new weapons under fire.