Thought about it last winter, a kentucky, or pennsylvania depending on who you believe, long rifle in .45.
But, I don't know anything about 'em, nor have I ever shot one.
Any thoughts, comments, or opinions?

They are a lot of fun to shoot. I would go with a .50 caliber, but if a .45 trips your boat then go that way. They normally are roundball rifles. And very accurate.

What are you plans with this rifle??? Targets, small game or larger game??? Have you considered flintlock or percussion??? How much money do you want to put into this gun???

Take a look at www.flintlocks.com
These are considered the most accurate out there...

I used a .45 back in the 70s, now use both a .40 and a .54 caliber flintlock...

I tend to call them American Longrifles as they were made up and down the east coast during the 1700s and early to mid-1800s...

Can't go wrong with that hawkeye. No debate necessary.

Well, I've got more ? than ! at the moment. The .45 seems more "traditional" in my mind, though w/ 2 other .50's it would make things easier to follow suit.
I suppose a flinter would be as traditional as it gets-and I am considering it, but have 0 experience here. I imagine it is much more "labor intensive" vs percussion?
For some reason I'm stuck on shooting PRB, more "tradition" I guess.
I don't really small game hunt anymore, but it would be a good idea to be able to take deer; I am mostly thinking plinking.
Just w/in the hour I sold my 30-06 as I really don't shoot it anymore, never really liked to. So, that's the beginning of the long-rifle fund.
Now, I happen to have quite a few Cabela points accrued and have looked at their offerings. The only 1:66 twist happens to be .45, disremember the model (Blue-ridge?) but, honestly, am unsure of the quality though, as I've read, they are Pedersoli-made.
I don't know, as I type a flintlock .45 seems the way to go...
I am absolutely open to input.