“Beauregard had 50 cannon and mortars.”
Brigadier-General G.T. Beauregard was reported to have 120 artillery pieces. The vast majority of those artillery pieces wee filed cannon and field howitzers used in land engagements and against land fortifications, but not as a substitute for the very large and difficult to transport coastal guns and siege guns of the type required to reduce a harbor fortification. The artillery used to attack Fort Sumter were the larger cannon, howitzers, and mortars with the range and projectiles required to defeat the harbor fortifications of Fort Sumter. Those artillery pieces numbered slightly less than fifty pieces. The vast majority of the more than 7,000 South Carolina Army and Confederate States Army troops reported to be present at Charleston, South Carolina were infantry regiments, mounted infantry or dragoons, and field artillery battalions or regiments, some of who served alongside the artillery battalions and regiments firing upon Fort Sumter
“According to your reasoning (you said he had between 3,000 and 6,000 troops), each gun had between a 60-man crew and a 120-man crew.”
You are being silly with that statement, because you should know already most of those troops were infantry regiments and mounted infantry regiments not involved with the firing of the artillery pieces.
Cite your source. Everything I’ve read said 50 cannon and mortars were used to assault Ft. Sumter. Also, cite your source that there were 7,000 Confederate troops engaged in the assault. There may have been 7,000 CSA troops in South Carolina, but on the banks and revetments in the assault? Sorry, no way.