The Pre-War boxes were black, but, due to fading and dye variations, some appear to have a purple hue.
Strangely, the transition from Pre-war style boxes to Post-War style boxes occurred in the immediate Post-War period, generally during the 1946-1947 period. By 1948, I believe all Pre-War style boxes were used up, and the dark-brown, pebble-grain, hinged-lid boxes with the buff interior and the dirty gold end labels came into general use, except for models with adjustable sights, which were shipped in the medium-brown, leatherette-grain, hinged-lid boxes with the dark green interior and the same style dirty gold end labels.
(Apologies to anyone offended by my "delivery.")