Cobalt Repeater

This is what you build the moment your first hardmode ore run pays out, and it exists to carry a ranger up to the mechanical bosses rather than through them. It shoots fast enough that ammo choice does most of the work, so jester or unholy arrows change its output far more than any reforge will.

Its ceiling is low. A Daedalus Stormbow off a Hallowed Mimic outclasses it without much effort, and the Hallowed Repeater is waiting on the far side of the first mech kill. Spend the minimum on it and save your coins for the weapon after.