This artillery battery was assigned to the Cavalry Division of the Military Department of West Mississippi during this period. Brig. Gen. J. W. Davidson was the cavalry commander of the Dept. of West Mississippi and was the expedition commander. The 1st Wisconsin Battery was assigned to the second brigade and was commanded by Lieut. Daniel Webster filling in for Capt. Foster who was on detached duty. On October 14, 1864, the battery was reduced to a four gun battery because of reduced number of enlisted men. The battery was serving as a horse artillery battery.

The official records for this period (late 1864) do not mention what type of guns were with the battery but Volume 52, part 1, page 49 mentions that the battery had six 10 pounder rifles on October 14, 1862. A 10 pounder rifle in 1862 would actually be a M1861 2.9" Parrott Rifle. Although I can't say exactly what type of guns the battery had, I can say that the Official Records do not mention the battery was reequipped with a differant type. So, I believe the best answer for you is the Parrott Rifle.
Hope this helps
Ron