Used in Weapons.con. If a hand weapon is made up out of many bones, then this property is used to connect one model part of the weapon (stored in a seperate .sm file) to the bone name found in the weapon's .ske file. For example, the No4 and K98 sniper rifles use this to attach a clip model to a bone named clip. This property is also used for the weapons' reload animation, located in animations/weapons/weapon name/animation file to make each piece of the weapon move separately.
Making custom bones for weapons is possible but requires custom animations as well.
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