Magical Crossbow.. too powerful?

I was looking up show notes for RFI and stumbled across this one in an old dragon magazine (40), and was considering it for one of my games.

Crossbow of Multiplication.

May be either light or heavy, and uses the range of fire of the proper class. However, the weapon creates its own bolts. These are treated as +0, +0 magic bolts but can hit any target capable of being damaged at all by physical weapons (even those, for example, which can only be hurt by +3 weapons or by blunt weapons). Bolts disappear after hitting or missing. On each shot, roll a 20-sided die for the number of bolts fired, subtracting 5. Results of 5 or less are treated as 0 (that is, there is a 25% chance the crossbow will fire nothing at all—otherwise, it fires 1 to 15 bolts). The bolts spread out in an even cone in a forward direction, from a single bolt straight ahead to 15 in a 90-degree cone. Therefore, unless the target is very wide or very close, no more than 1 or 2 bolts will strike a single target.

After reading it, I was like, this is way too powerful for a low level campaign. But then after reading it a few times, It isn't so bad. So it shoot a lot of bolts..big deal... Will it hit things? There is a 25% chance to no bolts come out and do nothing.  Otherwise 1 to 15 bolts come out to attack my target area, but unless its a big old fat monster, only a bolt or two will hit. So it gets a bonus for looking cool and seeming like an advantage, and double bonus it only will hit one target. Triple bonus is if you have a knuckle head in your group that fires this into combat, its going to hit the whole party lol.

The only advantage a player has on this item, is if they get put up against 5 monsters at once and get first attack or its a really large monster, like a giant or a dragon.

Thoughts?