I've bent a lot of M12 tang/shank,,what ever you want to call it,, to adjust the drop on them. I heat the shank up close to the rec'vr with an acetylene torch heat to red. Grab it with a plier & bend it. They bend easy.
Quick heat,,not so close to the rec'vr that you damage the blue on it.
It doesn't take a whole lot of adjustment of the shank to change the drop at the heal a bunch.
Then you have to re-inlet the stock to rec'vr inletting a touch when done as the top will hit before the bottom edge.
Not a big deal. The entire process takes about 30 minutes if you're tired.
M97's alter easily too.
I've never bent one w/o using heat. Just didn't seem like an easy thing to do.
The shank is a separate piece threaded into the receiver but still a stout one. Threaded into a reinforcement of sorts on the back of the M12. But straight into the back wall of the rcv'r on the 97.
You are putting a tiny bend in the shank itself this way,,the forward end of it that's threaded into the rec'vr doesn't move anywhere.
Make sure the shank is tightly threaded into the rcv'r before you begin or the heat can leave you with a wobbly, slightly loose,,but still usable stock mounting shank when you're done
A far as the forend is concerned,,seems like there was a short length forend slide for a few years pre WW2 offered on a Skeetgun or something like that. I had a 16ga in once w/one on but don't recall much more about it than that.
