anybody who's been in the military never mind combat does not carry two rifles. maybe a submachine gun or pistol but not another rifle. I very much doubt that you could randomly modify a military service rifle without comment from higher up's. Also I have seen alot of photo's suposedly of WWII in asia that were actualy later in malasia. Just saying.
It was quite often that when a barrel was shot out, it was easy to bend it 90 degrees to facilitate its removal. why bend it 90 iif iit will unscrew just as easily at 70 degrees? even when the rifle is 100 years old and the barrel has not been replaced once or more its not that hard to uncrew a barrel. bending a barrel 90 or 70 degrees prevents it from beeing used or misused again.
I would never rebuild or reuse a rifle that had been in a fire. heat treating goes right out the door along with safety. hot enough to burn of all the wood? no way.
interesting pictures but lets avoid turning speculation into fact.