I (like many of you) have cut plenty of milk jugs and water bottles with my swords. Those are good because they are free/cheap. What do you guys bash with your maces and war hammers? I have three blunt weapons now and I've not put any of them to use.

The cheaper and the easier to clean up the better.

Eric; I don't have a mace, but I have found that a fireplace log placed horizontally on a stump or other elevated object, is quite satisfying to bash with a warhammer. The logs I have used have had the bark on which yields a nice penetration effect when hammering (or spiking) through to the wood beneath the bark.

I had a lot of fun with coconuts but I would caution against the use of log, a buddy of mine destroyed one of his warhammers being a bit over zealous with it on an old cutting stand. though I suppose if you don't go overboard it should be fine.

I kinda like empty tin cans, just wash them out and go to it.
here's a vid of mine with some good (and bad) suggestions. we were having a little too much fun but no one got hurt and no weapons were harmed sooooo I guess it was ok.

http://www.youtube.com/watch?v=uy80BFTZNK0

Cabbage and apples, from horseback. Also a mixture of bearing grease and clay.