Dr. De Witt Bailey submitted his thesis for the Degree of Phd from Kings College in London in 1988. You may find this online.
“In a study which involves the use of both documents and artifacts, it is impossible to achieve a balanced view, and often impossible indeed to achieve a correct conclusion, without making use of both types of evidence. This was made strikingly clear to me when, after more than two years of organizing the documentary materials, in conjunction with access to various public and private collections of British military small-arms in this country and abroad, I was offered the chance of cataloguing the collection of British military small-arms at Colonial Williamsburg, in Virginia, U. S. A. Unlike any of the collections in England or Europe, not excepting the Tower of London's Royal Armouries, the Williamsburg collection contains several or many examples of a single type of arm. When these are closely examined and compared with the evidence in the documents, it is possible to draw a number of vital conclusions about the design and production methods which were quite impossible prior to such an examination. Although the documents do not suggest it, the products of the Board's system of manufacture reflect a far greater degree of unity, similarity) and precision than could be concluded from seeing only single examples. “
BTW, Dr. Bailey states the musket bore was .76 caliber in his books.