I do know that Winchester was capable of turning out close to 1000 a day.
S/n W-305 is dated 1915. It is one of the pre-production rifles sent to England for evaluation.
S/n W-201401 is dated 1917.
According to the little pocket reference that George Madis put out (available from the Winchester Museum at Cody), Winchester serials "passed 245,000".
I believe that Remington turned out a few less than Winchester. The BIG producer was Remington-Eddystone, of course. They could turn out 4,000 a day if they had to, plus spares as necessary. They actually did this over an extended period while building the US M-1917, which was essentially the same rifle. Hatcher gives production for the 1917 month-by-month and separated by factory: nice chart.
Hope this helps.
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