You have a +1 bonus to attack and damage rolls made with this weapon.
When you roll a 20 with this magic weapon, the target takes an extra 7 Piercing damage.
Note: According to the SRD, it is an extra 2d6 Piercing damage, although this is incorrect.
A Range weapon has a range in parentheses after the Ammunition or Thrown property. The range lists two numbers. The first is the weapon's normal range in feet, and the second is the weapon's long range. When attacking a target beyond normal range, you have Disadvantage on the attack roll. You can't attack a target beyond the long range.
You can use a weapon that has the Ammunition property to make a ranged attack only if you have ammunition to fire from it. The type of ammunition required is specified with the weapon's range. Each attack expends one piece of ammunition. Drawing the ammunition is part of the attack (you need a free hand to load a one-handed weapon). After a fight, you can spend 1 minute to recover half the ammunition (round down) you used in the fight; the rest is lost.
A Two-Handed weapon requires two hands when you attack with it.
If you hit a creature with this weapon and deal damage to the creature, you have Advantage on your next attack roll against that creature before the end of your next turn.