I busted that WhiteMountian myself. It wasn't wacked on a tree or anything else. The lock
screw was not overtightened. That particular stock
couldn't handle the beating.
The fact is I have a '70s T/C Hawken 50 [15/16]
that I bought new in '77. It has been abused in every possible way, no crack. Go figger?
So many people must have been playing softball
with their rifles that T/C did a mod that fixes
this. Replacement stocks have this mod too, just
in case you want to beat it on a tree.
The Seneca stock came that way, I bought it for parts. Kind of sad as other than the crack it is
a nicely figured piece of wood. No signs of any
external impact [leaves,bark,etc].
Soooooo, I will state as plainly as possible:
If you put a lot of powder under a heavy bullet,
it just might crack your Seneca or Cherokee.
P.A.