Don't head shots work best?
Anything upwards of 20mm doesn't need targeting that proper.
As the fine people at cracked.com found out (
LINK),...
![](http://i.crackedcdn.com/phpimages/article/7/7/9/97779.jpg?v=1)
However, since you're in a tank I suppose encountering burning zombies is not too much of a problem.
I'd also vote for canister. :)
Or, if you're crazy enough and the zombie crowd is big enough, how about ye olde chain-shot?
![](http://upload.wikimedia.org/wikipedia/commons/thumb/6/68/Boulet_ram%C3%A9_mg_5230.jpg/240px-Boulet_ram%C3%A9_mg_5230.jpg)
What was good against pirates can't be bad against zombies!
![Wink ;)](https://beyondthesprues.com/Forum/Smileys/clabIcons/wink.gif)
Hmmmm, silver canister against werewolves?