While Lew’s information about REAL production during WWII and after is likely correct, I thought I would peruse my Western catalogs a bit. The last Wartime catalog I have is dated January 2, 1942, and still shows a full commercial line, with the 9 mm offered in two loadings, both 125 grain, metal case and hollow-point soft nose. Does this mean they were still delivering the ammo, along with the rest of the line? Not in my judgment. I would not rule out some shipments, but it is unlikely that in 1942, with America’s real involvement in the war just getting off to a rocky start, that they would be relegating much production to commercial sales. Concerning bullet weight, my earliest Western catalog from the 1920s shows the weight as 124 grains, but somewhere along the line it changed to 125 grains. The weight change is absolutely insignificant except to those puzzled by weights shown on the packaging for this caliber. It is an academic question at best.
The March 7th, 1946 catalog, my next date, shows only one 9 mm load, the 125 grain Full Patch, and is the first of my catalogs to indicate that this caliber was only available in the Winchester line.The July 9th, 1946 catalog shows the same information. (By the way, I should stop saying “catalogs” as most of these are dealer price lists published by the factory). The January 2, 1947 price list shows the single load of 9 mm Luger as available only in the Winchester brand, as do all my succeeding price list up to my last from January 2, 1976. but the bullet weight had been dropped to 115 grains.
By the 1976 price sheet, all centerfire pistol ammunition, including blanks, were shown as Winchester brand only, even though the Price Sheet is a Western sheet, not Winchester-Western. There was one exception, and one can’t help to wonder if it isn’t a printing error. The .44 Magnum Revolver round with (Index 44MHSP) with with 240 hollow-point soft-nose bullet, is not marked as “Winchester only” even though the .44 Magnum with 240 grain Lead Gas-Check bullet IS shown as Winchester only.
The Winchester-Western brands have always been a bit confusing to sort out.
I hope this helps a little, especially in light of the actual production details Lew posted. I think that most of us know that appearance on price lists is not a guarantee of availability contemporary to that list.