CZ,
Never cracked a stock but had a 12ga Flues double when I was a kid (71-72) and crack the water table in the thin area on the right side. Still have the gun. Smith welded the action and its still running like the Eveready bunny with 1oz LP loads. Love the old Flues guns. Have 4 right now, one 12ga, two 16's and a 20ga. I think this sums it up real well

"With regards Ithaca Flues models and higher pressure shells, dumb idea."

Bill Johnson