lubbockdave:
From my point of view, if you're looking for a durable gun to roll tin cans or bust clods, and you're okay with a semi-auto...go for a "no-frills" Ruger MkII. They're hard to beat. If it's a revolver you're really interesed in...Ruger and S&W have some neat guns. Spend some time in a gun shop and see which one fits you best.
Good luck with your search...let us know what you end up with and how you like it!
Good Luck and Be Safe! ...Chris