8x57JS sporting load with GW headstamp

This hs will no doubt be well known to those 8mm Mauser specialists. The following hs is on SP sporting loadings and looks factory genuine ?

According to my White & Munhall, this hs was also on 6.35mm AP and was unknown in my edition. Jorion & Reigenstreif believes the “G W” represents Gustloff-Werke (Hirrtenberger).

Can anyone positively confirm this ?

Josef Mötz in his book lists this headstamp as:
GW Patronenfabrik Otto Eberhardt - Gustloffwerke, Hirtenberg / Niederdonau (auf Zivilpatronen um 1940 / on commercial cartridges around 1940)

Thanks Phil, I should have checked Josef’s books.