There were alot of small guns in the hands of Cav. and Inf. units (especialy in the Trans- Miss area) which were detailed from command to command and rarely mentioned as to there type, size ect. Being in the service of the Inf./Cav. often excludes them from Ord. Dept records also making them hard to track.

What caught my eye in your post was the Williams Rifled
statement. I have seen this report before and read it again and it does not mention them as rifled.

Bob