When the wine is bought up with the gifts it should not be in the chalice. The normal term for the container is “cruet”.
From the 2002 General Introduction to the Roman Missal (GIRM) which can be accessed from
romanrite.com/girm.html :
“118. The following are also to be prepared: …
c. On the credence table: … cruets containing the wine and the water, unless all of these are presented by the faithful in procession at the Offertory;”
“142. After this, as the minister presents the cruets, the priest stands at the side of the altar and pours wine and a little water into the chalice, saying quietly, Per huius aquae (By the mystery of this water).”
Unfortunately an
incorrect answer on this issue was published in the November 2006 Adoremus Bulletin: “To summarize: … the wine is poured into the chalice(s) which are brought to the altar at the Offertory already filled. The filling of these chalices with unconsecrated wine may take place in the sacristy, or at the credence table. Anything resembling a “filling ceremony” at the altar is definitely not in any way suggested, much less advocated by the approved norms.” The article is at
adoremus.org/1106Chalices.html .
Perhaps this has caused confusion.
I think it would be better to use the term “cruets” instead “flagons”. I think the wine cruet should have a lid to reduce the evaporation of alcohol from the wine. But unless I have missed the point, I think the USCCB information is OK.