Yes, that is the slot that I was asking about way earlier in this thread. I attempted to ask whether it extended past the end of the bayonet lug when the barrel is installed properly in it’s slot. But things got confused and I believe that we ended up discussing the slot for the actual bayonet on the under side of the stock. When you apply that slot to your diagram, we should have an answer I believe. Walt could possibly confirm this on an actual rifle also I believe.
The large slot at the forward end of the stock extends back from the front of the wooden stock, about 1 inch.... That slot is 5/16 " wide (the width of the bayonet lug that fits into that slot.)
Does this information answer the question?