USCCo 1918 .30/06
By 1922, USCCo. had virtually ceased to exist, due to cashflow problems due to the sudden end of the war and cessation of government contracts.(it was absorbed by Remington by 1923)
The cases may have been made in 1918, (as HS shows) and filled later...usually within a year, otherwise the priming compound would also be "out of spec" for Aircraft use.
The label "drawing number" may be 1922, and be a succession of "drawing" numbers, over time. It does NOT mean that the ammo was made in 1922.
It may have been "repacked" to clean up old stock...the different Powder types used could indicate this (cartridges from different Lots of Powder, repacked into new boxes, and re-Lotted...a lot if this happened after WW I.--this would have also happened to ex-belted MG ammo back from France.)
Only a research of the "Lot" numbers will give a definite date of completion...and that information has probably been lost since USCco went under.
Regards, Doc AV
AV Ballistics.