~Weapons Training + Blunderbuss
THAT'S using their numbers against them.
~Quickshot = 2 bolts per hero. Much better odds of taking a few down.
~Bottlenecking - If there's a lot of fences, position yourself so they have to go through a tight spot to attack you. Dwarves are some of the toughest models out there with 20 mm bases, meaning bigger guys (25mm) and horde bands have a hard time facing them in a tight spot. Doorways are your friend.
~Ropes & Hooks - if you can reroll every climbing test a hero has to make, you have a much better chance of getting the higher ground and sniping more. At 5gc & common, no reason not to.