Given equal precision and alloys used in construction a musket will jam less than a more complex gun. However a musket and bullets built with 1700 technology/precision will jam more than a gun built to the best best modern standards standards (though there are some pretty bad modern guns out there too that may not stack up so well).

A bolt action is simple compared to any semi-automatic gun. Particularly if it is a single shot bolt action thus dispensing with the complexity of a magazine feed.