Be very careful when using a locking type nut. These items are ONE TIME ONLY items.
Once you remove them, they are done. It may well feel like they are locked the second time, but they will not be sufficiently locked. Threads can be destroyed during the first removal making them unsafe.
Lock nuts or "star" nuts will have a diamond or some sort of funny pattern on them to let you know they are locking nuts.
If all you have are the metal locking nuts when you reassemble a sprocket, you'd be better off using a new grade 5-8 bolt and using liquid loc-tite.
BTW...Nylocs, or nylon locking nuts, are ONE TIME USE ONLY as well. Never kid yourself and feel they are fine for a second use. They aren't.