One could put a dent in virtually any vintage gun depending upon how hard you're whacking it into a tree, how hard you've fallen or how unlucky you've been. There are oodles and oodles of vintage doubles with <.025 MWT that have survived a century or more of usage with nary a dent.
Here's what one vintage gun dealer opined in a post in these pages several years ago:
http://parkerguns.org/forums/showthr...8456#post78456