This is just a little querk I've noticed while shooting the different types. The multiple Springfields that I've used have a much smaller half-cock than Enfields, making firing on the battlefield much easier and faster. Plus, the Enfield is a lot cooler looking!
You asked earlier if either one of these guns would be acceptabe for either side. The answer is the Enfield. It was the most common CS gun and 2nd most common US gun (after the Springfield). However, if you join a CS and have a Springfield, it would be fun to tell the onlookers that you took the gun off of a dead US soldier becasue it was better than the gun that you brought from home.
Another thing that kinda gets me steamed at some reenactments is that when the regiment stacks arms, it is WAY much more rag-tagged looking than it should have been (at least for US troops) because of the innaccurate mix of Enfields and Springfields. Usually, a regiment used the same gun. I suggest asking the unit what gun the actual unit used in the war and get that, just so you don't make the same mistake I did!
I remain, highly esteemed Herr Reenactor, your devoted
Founder: Civil War Club @ Grand Valley State University
President '07-'08, '09-'10
Living Historian: 1860 Farmer, Susquehanna Plantation, Greenfield Village