Yes. package yourProjectile::onCollision(%this, %obj, %col, %fade, %pos, %normal) and write a check for %obj having the item you want to remove, then remove it. To see how to properly remove items, look up item-removal/adding events like addItem.
a package for yourProjectile::oncollision isn't actually necessary; it only is if you're packaging projectileData::onCollision (the lowest level function)