Can the Hunter subclass use their Volley feature with a melee weapon?

Question

The Ranger subclass in D&D 5e, Hunter, has an 11th-level feature called Multiattack which allows them to pick Volley or Whirlwind.

Volley.
You can use your action to make a ranged attack against any number of creatures within 10 feet of a point you can see within your weapon’s range. You must have ammunition for each target, as normal, and you make a separate attack roll for each target.

Is there anything that would allow a Hunter to use any melee weapons, such as a glaive, to perform a "volley" of stabs by targeting a point within their weapon's reach (such as in front of them) and targeting the creatures within 10 feet of that point to perform a "range attack" despite using a melee weapon?

Answer 1

No.

The quoted rules say (emphases mine):

Volley.
You can use your action to make a ranged attack against any number of creatures within 10 feet of a point you can see within your weapon’s range.

The feature requires explicitly a ranged attack, moreover it mentions the weapon's range, not the attack's reach.

The Whirlwind attack option does not allow it either: one cannot attack enemies at more than 5 feet.

The text of Whirlwind Attack says (emphasis mine):

You can use your action to make a melee attack against any number of creatures within 5 feet of you, with a separate attack roll for each target.

Hence, even the glaive's reach is 10 feet, a Ranger with Whirlwind Attack can attack enemies only within 5 feet of them.

Answer 2

You can only use the volley with ranged weapons that use ammunition

The volley has two conditions for its use

1. it must be a ranged attack
2. it must use ammuntion

You can use your action to make a ranged attack against any number of creatures within 10 feet of a point you can see within your weapon’s range. You must have ammunition for each target, as normal, and you make a separate attack roll for each target.

A pure melee weapon, such as a glaive, can not be used for the volley, as it violates both conditions.

While some melee weapons, such as a dagger, light hammer, or handaxe have the thrown property, which allows you to use them for ranged attacks, they do not have the ammuntion property, so even those weapons cannot be used for a volley. Page 146, PHB:

Ammunition. You can use a weapon that has the ammunition property to make a ranged attack only if you have ammunition to fire from the weapon. Each time you attack with the weapon, you expend one piece of ammunition. Drawing the ammunition from a quiver, case, or other container is part of the attack.

While this is the technical rules-as-written answer for thrown weapons, check with your DM. They may be up for allowing you to throw multiple daggers or such, in case you have them in a belt to throw. This should not be unbalancing, as a bow tends to deal as much or more damage than these weapons, and either one will suffer disadavantage if used in close combat, so it is more of a flavor question to allow this or not.