The anonymous
As are often very difficult to pin down precisely; I agree with
Meepzorp that this is not the Cr 195/1 "Ass"
As. The left-ward angled thing is likely the "
corvus" = boarding bridge, or the deckhouse, or both smudged together and often vaguely depicted to begin with.
There will not be any "pellets" on an
As, and I do not see any. Pellets were features of the smaller factions.
The
weight also likely makes it earlier than the "Ass-
As".
I think there is a trace of "ROMA" below the galley.
There could be something else, but it is a
bit hard to say. My guess is that there aren't any of the specific
symbols that make out a distinct issue.
You might want to take a look at
http://andrewmccabe.ancients.info/RRC056.html for a detailed look at these anonymous coins and to get a sense of where your coin fits in. Perhaps the "G" groups, G4 maybe, but don't expect a definite match as these are often poorly struck and worn, so very ambiguous. The examples are far sharper than the vast majority of specimens. The article is a a great resource, worth the time even if you don't come close to a match.