I know this has probably been asked a million times about 03A3's but.....

[Rick the Librarian]

Good point, Rick, but we're both really just guessing without more info. If his grandfather wasn't inducted until, say, 1943, it's all moot anyway. I had in mind a single digit infantry division, but couldn't locate the file. Turns out I was thinking of the 4th DIV which was also an RA unit and also embarked rather late. This report is from December '42. Since the 4th DIV still had '03s a year after US entry, it's not implausible that a similar early mobilization/late departure unit was in the same boat. All I need to do is win the lottery and I could add this question to my National Archives wish list.

View image: springfield barrels 4th infdiv 12 28 42 001

The OP may have to be content in the knowledge that his grandfather would have received familiarization training with all small arms, so he at least handled everything. Depending on when the promotion to sergeant happened, the 03A3 would still seem to be the least likely candidate. But that too is based on playing the odds in the absence of facts about the division.

Interesting memo, but it doesn't say whether the Springfields were "here and there" or equpped whole units. Keep in mind that the infantry units (which, I believe, made up only about 50-60% of an infantry division. As I'm sure you know, there were a large number of support units - engineers, artillery, MP, etc. that could have retained M1903s. I have some charts of TO&E but, unfortunately, do not differentiate between M1903s and M1s. As an "educated guess", I would estimate that several hundred M1903s remained in each division, at least until the M1 carbine became more common.