Simple answer is no, it is not period correct to install a liner. If you are reenacting, don't install one.
If you are not a reenactor, then do it if that's what you want.
I'd have to disagree, but only slightly, with my neighbor, John. A touch hole liner is not correct for the vast majority of Bess in history....
As reenactors, we probably shoot the bess or charleville a lot more than they did in the flint era, even when the soldiers were in a regiment that regularly practiced shooting at marks. I say this as it's not uncommon to fire more than 24 rounds during a single day's reenacted battle, and a weekend often has two days' worth of battles. Go to four battle events a year and your Bess is seeing way more firing in a year than it's ancestor probably did. Use that musket for 20-30 years and....
Add to that the fact that many of the lads opened up their touch holes to 1/8" back in the day as they thought it gave them surer ignition, and that the retiring guys are selling off muskets with 20-30 years of service, and you get a lot of vintage muskets out there now with very worn touch holes, that will self-prime if you close the frizzen on an empty pan, and simply pour the whole charge down the barrel...even if you use 2Fg. :shocked2:
So..., while you have a flash guard when reenacting, if all you ever do is launch blanks, no need to fix the touch hole, but if you ever shoot ball, you probably want to tighten that touch hole up a bit, if it's worn.
LD