Quick fill cap for a toy water gun

The present invention is directed to a quick fill cap for a toy gun capable of discharging an output stream of liquid, the toy gun having a liquid reservoir for storing a quantity of liquid and a fill port for depositing liquid in to the liquid reservoir. The quick fill cap may include a cap portion having a throughbore, with the cap portion demountably attaching to the fill port of the toy gun when the cap portion is disposed thereon, and forming a substantially air-tight and water-tight seal with the fill port. The quick fill cap may further include a one-way valve connected to the cap portion proximate an opening of the throughbore, wherein the one-way valve is disposed on the interior of the liquid reservoir when the cap portion is demountably attached to the fill port, may allow liquid to flow from the exterior of the liquid reservoir through the channel formed by the hollow funnel and the throughbore of the cap portion and into the reservoir, and may prevent liquid from flowing from the interior of the liquid reservoir through the channel formed by the throughbore of the cap portion to the exterior of the reservoir.