So for a civilian lock, you want to use leather, BUT you want the back of the flint to rest upon the jaw screw. You want the rough side of the leather against the flint.
I use cowhide or elkhide, and there are two basic methods. The top method in the illustration puts the jaw screw through the two holes when the leather is folded and placed in the cock jaws. This keeps the leather from being lost IF the flint slips out. The second illustration simply leaves an open groove for the back of the flint wrapped within the leather to rest naked upon the jaw screw. I've always found more reliable sparking this way, and as extant jaw leathers and leads have such an opening, this seems to be correct.
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