Hi,
The pattern 1730 was the first Brown Bess and it was issued from about 1730 to the early 1750s. It was replaced by the pattern 1742 but was still issued to Provincial troops and soldiers serving in North America well into the 1750s. I suspect your lock reads "Iordan" for Edward Jordan and the date is likely after 1740. British ordnance and soldiers rarely called the musket "Brown Bess". It was almost always referred to as the "King's pattern musket" with updated versions called "new" patterns compared with the "old" pattern. The 1730 was issued without extensive field testing and flaws in it showed up immediately. The biggest issue was the trigger guard was too weak. It was upgraded with new guards, new lock, steel rammer, etc all through its service life so surviving 1730s often show a lot of variation in components. You can see strong Dutch influence in the musket. That is because Andreas Dolep, a Dutch immigrant gunsmith working in London, had a strong influence on the design. The initial prototypes from which King George I selected the official pattern were made by Lewis Barbar, a French immigrant gunmaker working in London. He made a batch with 42" barrels mounted in brass, and a batch with 46" barrels mounted in iron. King George, who was German, selected one of the long prototypes but wanted it mounted in brass. That brass mounted gun became the 1730 King's pattern musket. The weak trigger guard is because the iron mounted version would have been plenty strong but when the design was made from brass it was too weak. The irony is that the iconic British Brown Bess musket, symbol of British imperialism, was mostly designed by an immigrant Dutchman, first made by an immigrant Frenchman, and selected by an immigrant German king. Oh those darned immigrants!!
dave