gun, arms
銃 centers on handheld firearms: a gun or weapon that shoots. The broader sense of arms covers military weapons in general.
銃 combines 金 (metal) with 充, which likely contributes the sound ジュウ. The metal radical points to a weapon made of metal.
Metal 金 on the left and 充 on the right: picture a metal tube being filled with gunpowder, ready to fire.
For ジュウ, imagine a gun that shoots juice instead of bullets: juice -> ジュウ, and the metal weapon sprays juice everywhere.
gun; firearm; small arms (e.g. rifle, pistol, etc)
pistol; handgun
shooting; gunning (down)
bullet (from a rifle)
death by shooting
small arms
gun point; muzzle
rifle; small arms
machine gun
bayonet
gun barrel
sound of a gunshot; report of a gun
hunting gun; sportsgun
gunfire
matchlock; arquebus
emplacement
guns; firearms
gunshot wound
stock (of a gun); gunstock
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