I recall reading for a short time at the national matches(1903 rifle) they were dipping the tips of bullets into oil, concept similar to molly coated bullets. This devolved into soldiers dipping the whole 5 round clip in oil. Brass cases failed to grip the chamber walls , bolt lugs cracked and people were injured which ended the practice. Our above caption is most likely the caption writer not knowing what he is talking about.

In early development of the garand there were thoughts of lubricating cases with wax also the experimental m1924 Garandicon rifle had a internal oiling pad. see page 64 of Canfield's garand book. Bob S. can expand on this further.