Barrage of Expendables

• WWizards of the Coast2013-07-01
  Official Ruling
  Barrage of Expendables deals the damage, not the sacrificed creature. Notably, that creature having deathtouch or lifelink provides no additional benefit.
• WWizards of the Coast2013-07-01
  Official Ruling
  Because targets are chosen before costs are paid, it is possible to choose a creature as the target of the ability and then sacrifice that creature. The ability won't resolve when it tries to resolve and no damage will be dealt.

Rulings via Scryfall