Yep, locks and barrels were the expensive bits.
That is why we can read stories about guns that were remade from percussion to pinfire to centerfire.
I think that lower grade guns would still have been the pride of their owner and may have been upgraded.
Rebounders took over the industry and from what I have read, there were a few years where 'smiths made a living (ok thats an overstatement) upgrading lots of guns of differing grades.
It is hard to find a non-rebounding centerfire hammergun from that era.
