as long as the coin isn't bent (i dont think it is) that rim weakness is probably from the dies being slightly misaligned. the dies would have been slightly closer together near the date and a bit further apart around 1 or 2:00. there were a lot of die alignment issues in the 1850s and that type of issue is much more apparent on small coins than it is on larger pieces like a large cent or a silver dollar. you can find modern Roosevelt dimes that are misaligned pretty easily.
I collect low grade large cents. I currently have >230 Sheldon varieties and >235 middle date Newcomb varieties.