I'm trying to learn more about the four heavy artillery regiments that were assigned to the department of Richmond in 1864 . These were the 10th, the 18th, 19th, and the 20th regiments of heavy artillery

I want to find out what they were armed with. According to the report of Colonel Walter H. Stevens on March 1, 1864 they fought on the outskirts of Richmond with rifles against raiding union cavalry
Does this mean they were sometimes armed with rifles but also served as cannoneers?

Bryce