It would depend on the model ( Hawken, Renegade, New Englander, Encore, Triumph, ect ) and condition. The best way to determine actual value is to search the online auctions, such as www.gunbroker.com and www.auctionarms.com or even www.proxibid.com enter your details in the search and see what has SOLD and for how much. if there is nothing current try the archives of past sales of items sold. Don't forget condition has allot to do with value, so compare apples to apples.
try the Kittery trading post
Most black powder bores have a twist that is relatively slow. Say 1:36 or 1:50. They were 1:48 twist in 45 and 50 caliber
You will have to specify if you are referring to black powder, rim fire or center fire and the weight of the projectile
You will have to tell us if you are talking about black powder or center fire.
50-350 depending on specifics
You can download manuals from the Thompson Center website listed here in the related links, you can also find a phone number there to request a hard copy. You will need to know the model. In this case the 25th anniversary Hawken, same specs apply as the standard Hawkens rifle.
Depends on if you are talking black powder, rim fire or center fire. 300-25000 ft is ballpark .
1gran per caliber
You can contact Thompson Center Customer Service through their website for help. They are still in business, you know. BTW, really good rifles.
An excellent or like-new specimen (be sure to check for rust inside barrel) would be worth $200-250. A more beat-up specimen would be 100 to maybe 150.
Depends on the caliber. A .45 caliber pistol uses about 40 grains of black powder. Contact the maker's website and download the owner's manual for YOUR gun.
You will have to call TC to find out.