Rifle grenade
A rifle grenade is a form of grenade that utilizes a rifle as a launch mechanism to increase the effective range of the grenade. The idea was first developed in World War I and continues to this day. Many armies have replaced rifle grenades with dedicated grenade launchers.
Advantages and disadvantages
The modern rifle grenade remains arguably a more effective weapon than the grenade launcher because:
- Rifle grenade warheads are larger (and thus more effective) than typical grenade launcher rounds; and,[citation needed]
- A rifle grenade can be fired from any field service rifle, thus making virtually any soldier into a "grenadier" at the drop of a hat, whereas grenade launcher rounds can only be fired from grenade launchers. The grenade launcher also adds the burden of the launcher to the service-member's load and in the case of under-barrel grenade launchers, to his primary weapon as well.[citation needed]
Offsetting these strengths are low velocity with an attendant arcing trajectory, and very high levels of recoil. These drawbacks combine to make rifle grenades extremely inaccurate weapons. Lack of accuracy is the main reason why most major militaries have opted to replace rifle grenades with dedicated grenade launchers.
Operation
Historical rifle grenades used two different launching mechanisms:
- A stick that fitted down the interior of the rifle barrel;
- A cup or special adapter that fitted on the end of the rifle muzzle.
For both these methods, a blank cartridge was required; in the former case, it propelled both the stick and the grenade. It was found that repeated use of a rifle for launching grenades by this method caused damage to the barrel, which is what lead to the cup/adapter technique. The need to load a blank cartridge at the same time as the rifle grenade proved difficult in combat. Attempting to use a live round with either a stick or cup grenade launcher would have disastrous results.
The problem with having to load special ammunition has been addressed with the modern concepts of the "bullet trap" and "bullet through" rifle grenades. The former "traps" the live ball or tracer round within the grenade, and uses its energy for propulsion. "Bullet through" grenades, as for example the French Viven Bessieres (VB)used in WW-1, have a hole through the middle that permits the passage of a standard bullet, and use the expanding gas to propel the grenade. Both these methods remove the need for a special blank round to be loaded to launch.
Rifle grenades can be of any type as the more conventional hand grenades. However, two types predominate — fragmentation grenades, for use against personnel; and shaped charge for armoured vehicles. Rifle grenades may be time-fused, so that they detonate at a fixed time after firing, or impact-fused, so they detonate upon impact. Generally, antipersonnel grenades would be time-fused, and anti-armour grenades would be impact-fused.
Often, special sights that attach onto the rifle to provide aiming for the grenade's particular ballistics are employed. Since rifle grenades usually travel at low velocities with very high trajectories, their range is measured in tens of yards (meters). The maximum range of most rifle grenades was about 200 yards (180 meters). Rifle grenades are often fired at angles greater than 45 degrees, allowing them to drop down at steep angles to enter trenches, or to hit targets behind cover; the steep angle also increased the time of flight, to give the fuse more time to burn, so it would detonate as soon as possible after reaching the target. Firing at lower angles was useful for placing grenades through windows or other vertical openings.
History
Rifle grenades were common during World War II, but by the late 1970s they were largely replaced by designated grenade launchers. These grenade launchers generally took form of independent firearms (such as the M79 grenade launcher), or as an attachment to an assault rifle (the most common example being the M203 attached to M16/M4-family of rifles).
Today, there is a return to the concept of the rifle grenade, such as the M16's SIMON breach grenade and the IMI Tavor's "Rephaim" advance grenade. Modern combination doctrine designates a certain percentage of grenadiers, or soldiers equipped with a grenade launcher or combination rifle/grenade launcher. The criticism of this doctrine is that if the grenadiers in a group are disabled or separated from the group, then the group has completely lost the grenade launcher as a heavy fire support. With rifle grenades, each soldier would be equipped with a small number of grenades, so every individual soldier could utilize some form of heavy firepower.
Legal issues
In almost all countries, grenades are illegal for civilian ownership, though dummies (inert grenades with no fuse, detonator or explosives) are usually legal.
In the United States, rifle grenades are covered under the National Firearms Act as "destructive devices". A civilian could legally own a grenade in theory, but the requirement of a police chief's signature in certain places often makes owning such items legally nearly impossible.
Rifle grenade launchers are not subject to the National Firearms Act, although stand-alone grenade launchers may be, and rifle grenade launchers may be regulated by local law.
