I'm no expert on pre war barrel striking but.......
I find it interesting that "skilled" workers would leave such deep scoring in the finished barrel surface.
It doesn't need bright lighting or flash photography to see it either, it stands out like a third ball on a greyhound!

Also, a flash was not used to create those photos IMO.
400, go to Curls link or the original at Cabelas, take a look at the "T" in "ST" in the 13 KING ST address in the photo showing the folding sights, and magnify it.
It has a score in it big enough to have been made by a D9 Cat rather than a barrel file!

Truth is I think the photos may be making it look a little rougher than it really is.
Photos of rifles can be a little deceiving at times.