If it helps, here is the crown of a 3.31million M1903 that I've been cleaning up this week.
It is a replacement barrel stamped S.A./escutcheon/5-42. From what I read, the square cut and chamfer crown are common in the replacement barrels as apposed to the rounded crown of regular production. Your's looks a bit deeper than mine.
Attachment 110647Attachment 110648
The replacement barrels are "Type 6" in Poyer, and he reports "original installation" years as 1942-1945. Replacements should have a front sight collar similar to the 1903a3 with a notch for a fixed stud key, but still with the dovetail base. Replacements will be marked HS (High Standard), JA (Johnson Automatics), circle S for Sedgley or SA Springfield Armory. Curiously, the reported original installation of SA replacements was only 1944-1945. However, I have seen many Remington receivers with SA 1942 replacement barrels - including mine. The ordnance escutcheon bomb on these is always of the earlier type (1919-12/1941), but they have the keyed base with dovetail instead of just the pin. I have a few theories about replacement barrels and dates.
I'm sure all the eagle eyes will spot it - I have already made note of the two dings in my crown.
Also, the star-gauge marking looks like a circle with 8 points around it.