A barrel shroud is an external covering that envelops the barrel of a firearm, to prevent unwanted direct contact with the barrel. Moving coverings such as pistol slides, fore-end extension of the gunstock/chassis that do not fully encircle the barrel, and the receiver of a firearm itself are generally not described as barrel shrouds, though they can functionally act as such.
An MG-42 medium machinegun with a fully shrouded barrel.
An L85A2 rifle with a partially-shrouded barrel
A Winchester Model 12 combat shotgun with a barrel shroud and attached bayonet.
Handguard
A gunstock or often simply stock, the back portion of which is also known as a shoulder stock, a buttstock, or simply a butt, is a part of a long gun that provides structural support, to which the barrel, action, and firing mechanism are attached. The stock also provides a means for the shooter to firmly brace the gun and easily aim with stability by being held against the user's shoulder when shooting the gun, and helps to counter muzzle rise by transmitting recoil straight into the shooter's body.
An early hand cannon, or gonne, supported by a simple stock
A thumbscrew-adjustable check rise
M16A1 cutaway rifle (top) and M16A2 (below) with a "straight-line" stock configuration
Gun stock construction on a lathe from the 1850s (photo c. 2015)
