Chambers is hard to beat his guns are well researched and he has some early ones from other schools as well, I would suggest that if you are developing a specific persona/time period/area that some research on your part may be in order as these factors may sway the choice of a "correct" gun, do study the originals as much as possible some builders stretch history a bit to capture a wider customer base.I have Chambers Early Virginia smoothrifle which "could" date to 1750 and an Early Lancaster that "could" go back to 1760, barrel lengths for the early guns could be from 36" to 48" and bores would be mostly .50 and larger, barrels would likely be swamped, single triggers most common, wood patchboxes or wide brass type, less ornate than the later types, or no patchbox would also be proper, these are generalities of course but if you look at the ealy guns and compare with the later "Golden Age" and Federal period ones you will see some obvious patterns.