I would assume (yes I know what that does) that the majority of Sumters guns mounted prior to Anderson's arrival were pointed out to sea and were of little use in counterbattery fire towards the land batteries of Charleston Harbor. Some probably were aimed at the channel and therefore could have been used against Fort Moultrie.
In any case if his guns were pointed to the sea he may well have not been able to give assistance to the "Star of the West" in January. His guns may well have been pointed in the wrong direction to fire on the batteries that were firing on the "Star of the West". That is the reason I was asking about the direction of the 5 guns Anderson had mounted while he was inside the Fort. Were they mounted in a position to give support to another attempt?
I was wondering if the 5 guns that Anderson had his men to mount after he occupied Fort Sumter were aimed at the batteries other than Moultrie, or maybe better at Moultrie since the greatest threat to ships coming to aid Sumters garrison would have been from Moultries Guns or Johnson island. If I remember correct that Fort Sumter did intially reply to the shelling at first. I may be wrong. But if so Anderson may have ordered them to cease fire when he realised that the ships waiting outside the Harbor were not making a run in to dock.
If that were the case (an we know that confederate officials visited Fort Sumter to talk to Anderson several times during that period and possible have been able to observe these changes) these changes in gun positions could have been interpreted as being hostile in their nature.
5 large caliber guns would have been about the number of guns that 85 men could have effectively fully crewed and managed any way. If I am remembering correct it took about 12 to maybe 15 men each on a gun of that size to turn and move into position to load and aim the weapon. The rest of Sumters guns would have been useless anyway.