At some points during the war it's said that the Quartermaster's Corps had close to 200 separate types of ammunition to supply to the troops.
I'm not sure if that is just small arms ammunition, or if it is small arms and artillery.
But, anyway you look at it, it's a ton of stuff to get out.
That said, and I've said this several times over the past few weeks, is that the Union armies did a phenomonal job of getting the correct ammo to the troops in sufficient quantities, and when they needed it.
The Quartermaster's Corps, the military railroads, and the military telegraph authorities all quickly put into place some amazingly novel and innovative logistical processes to streamline supply and to make sure that those troops who had non-standard weapons got the ammunition they needed.
Sometimes it was simply by brute force -- Ok, you've got 20,000 Springfield .58-cal rifled muskets. Here's ammo for those. And just in case, here's ammo for the .69 caliber smoothbore, some Burnsides ammo, and what the hell, take some Smith carbine ammo, too.
Other times calvary units would telegraph that they would be at a certain rail head in X days, and that they needed X, X, and X, and their supplies would be waiting for them when they got there.
Yes, the Civil War weapons and ammunition situation was an interesting one. But it wasn't quite as catastrophic as it would appear that it should have been.
"The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza
Baby Jesus cries when the fat redneck doesn't have military-grade firepower.