Jeffrey:

I assume that you got the service information from his form DD-214. This usually lists the service in chronological order. MM2 is "Machinist Mate 2nd Class", which seems consistent with the DD-214 info. AGC Brooklyn is the Armed Guard Center, Brooklyn. DD-214 does not always (maybe never?) list individual ships he was assigned to while he was at AGC Brooklyn. Men were assigned to the AGC, and the AGC would assign men to specific merchant or transport ships as needed. From the view of the Navy, his service station at that time would be the AGC, since the merchant ships are NOT Navy Fleet ships.

Landing Craft and Tugs are part of the fleet, and they do show up on the DD-214.

If you had his complete service record (which is available to next of kin), there would be additional documents that show what merchant ships he was assigned to.

For clarity, the Merchant Marine is not part of the Navy. The Merchant Marine is the "civilian" (meaning non-Navy) crew of the merchant ship, just like any merchant ship today. The Armed Guards were part of the US Navy, and they served on the merchant ships to man defensive guns that the Navy put on the merchant ships. Armed Guards also supplied signalmen and sometimes radio operators. So a given ship would have both the merchant marine crews to run the ship, and the Armed Guards provided the crew to defend the ship.

Some men spent the whole war in the Armed Guard, others spent only part of it. Sounds like your grandfather spent some time assigned to the Armed Guard, and some time assigned to "fleet ships".

I applaud your effort to hunt down this information. I did the same thing for my father's service. It is not easy, and takes a lot of patience!

Let me know if you have other specific questions, and I'll try to help.

Regards,

Rick