The online sources I found differ!
Per this source:
http://usacac.army.mil/cac2/cgsc/carl/download/csipubs/gudmens.pdf (p. 17, last paragraph): "The Union and Confederate forces had artillery parity at Shiloh; Grant had 119 cannon and
Johnston had 117."
Per this source:
http://www.britishbattles.com/abes/1862/shiloh.htm,
the Confederacy had 120 guns. (This source also has a much larger number of Union cannon, 150 for Grant.)
Per this source:
https://books.google.com/books?id=D...r confederate artillery pieces shiloh&f=false:
The Confederates had 23 batteries. 1/3 were 4 guns, 2/3 were 6 guns, plus one battery with 7 guns (the extra gun was captured in Kentucky). Doing the math, subtracting the 7-gun battery from the total:
1/3 x 22 = 7 1/3 x 4 = 29 1/3 cannon in four-gun batteries
Since we can't chop up a cannon, let's try rounding:
22 x 1/3 = 7 four-gun batteries, x 4 = 28
22 - 7 = 15 six-gun batteries, x 6 = 90
1 seven-gun battery =
7
Total guns in 23 batteries 125
Per the first two sources above, this is probably too many. If we figure one more four-gun battery and one less six-gun battery, the total is 120, which agrees with the British number above. But this is verging on guesswork!
Per footnote 56 to the Wikipedia article,"Battle of Shiloh," "Historians disagree on the number of artillery pieces the Confederates massed against the Hornets Nest. Cunningham, p. 290, accounts for 51; Daniel, p. 229, argues for 53; and Sword, p. 326, and Eicher, p. 228, report the traditional count of 62, which was originally established by battlefield historian D. W. Reed." Of course these are not the total number used in the battle, but this footnote does illustrate differences in numbers.