In Afghanistan, the Taliban has learned that the safest way to attack foreign troops, is at long distance (at least 300 meters away). Thats because most foreign troops are armed with 5.56mm assault rifles. These are very accurate, and deadly, at under 200 meters. But beyond that, the 5.56mm bullet rapidly loses accuracy and hitting power. So the Taliban will set up a long range ambush using one or more 7.62mm machine-guns, 7.62mm rifles (preferred by snipers and sharpshooters everywhere, but in Afghanistan this often means a decades old bolt action weapon) and RPGs (rocket propelled grenades.) If available, mortars are used. But if the foreign troops come after you, the mortars often have to be abandoned in order to get away.
The real damage from RPG fire is the fragments from the exploding grenades. Even the anti-tank round (the most common fired by the RPG) would throw out wounding fragments for 3-5 meters (10-15 feet). These rarely killed, but troops were often wounded in the arms, legs and face, and often put out of action for a while. But most armies, and irregulars, like the RPG because it is cheap, easy to use and very effective against troops lacking protective vests and helmets. The RPG is also cheap. The RPG launcher costs anywhere from $100-$500 (lots of second hand stuff out there.) The most common RPG ammo is the anti-tank rocket and these go for $50-100 each. Costs add up, however, as you have to fire a dozen or so rounds to develop some accuracy. Unlike the launchers, RPG ammo doesn't get cheap, unless some wealthy nation is flooding an area with it, because the ammo gets used up and the launcher does not. Without much practice, a user can hit a vehicle sized target most of the time at ranges of 50-100 meters. As an operator fires more rounds, he becomes capable of hitting stationary targets at up to 500 meters, and moving targets at 300 meters. It's this last skill that has made the RPG dangerous against helicopters. A lot of Taliban cash goes to buying RPG ammo.
The Taliban also like using the RPG as a form of artillery. Get a bunch of RPGs firing at the same area say, 500-1,000 meters away, and you will do some damage to any people walking around. The rather more rare (and expensive) anti-personnel RPG rockets will spew out fragments up to ten meters (30 feet) or more.
The foreign troops have learned to adapt. For example, British infantry squads in Afghanistan have learned to adjust their armament to the mission. For example, when the troops will not be travelling long distances, over rough terrain, and expect to encounter armed resistance, they will carry more firepower, including more long range weapons. Thus an eight man squad will go out with two men armed with L85 5.56mm assault rifles (one equipped with a 40mm grenade launcher), two with 5.56mm LSW automatic rifles (an L85 with a longer and heavier barrel), two with 5.56mm FN Minimi machine-guns and two with FN-MAG 7.62mm machine-guns. The latter are particularly useful if the squad is fired on by an enemy several hundred meters away. These "heavy" squads are also receiving the new 7.62mm L129A1 semi-automatic sharpshooter rifles, and one of those will often be carried along as well. Most squads already have one man armed with the existing FN-FAL 7.62mm sharpshooter rifle. Thus the heavy squad would go out with only one standard L85 assault rifle, and that one carrying a 40mm grenade launcher attachment under the barrel. The 40mm grenades are officially accurate out to 400 meters. But an experienced grenadier can put rounds on targets at twice that range.
Under normal conditions, the squad is armed with four L85s, two LSWs and two FN Minimis. One L85 has the 40mm grenade launcher and, especially in Afghanistan (where longer shots are more common), one L85 is often replaced with a 7.62mm sharpshooter rifle. In some cases, one or both of the LSWs are replaced by a 7.62mm or .338 sniper rifle.
This informal upgrading of squad firepower is nothing new, and was quite common during World War II, where even captured enemy weapons (particularly automatics) were carried instead of the standard infantry rifle. American, and other NATO, infantry, are making similar adjustments. This, of course, depends on their commanders obtaining more 7.62mm rifles and machine-guns. But even the commanders are well aware of the range issue, and have been making quite a lot of noise about the need for longer range weapons. There is also more demand for 7.62mm ammo, so that troops can practice their long range shooting.