pardon for resurrecting a slightly old thread.
peep sights are **SO** much more consistently accurate than u/post sights, but perhaps not so good for early 18th century warfare where there was little aiming required of the weapon of the day - the smoothbore. buffalo hunters of the early to mid 19th century used them on both cap and flint lock rifles to down far off plains bison. moving from caplocks to bpcr long guns, the simple peep got a major upgrade with vernier tang and soule windage, and then a hooded front globe.