I want to thank you for your interest in my for sale list. The most asked question was what does the T- mean beside the barrels?
As every one knows TC started out in 1967....here we are in 2006 and over the years there has been many improvements-changes that myself and other collectors use to determine production dates. Actually this information is the kind of stuff you learn when being a member of the TCA (Thompson Collectors Assoc). If you would like more info about membership, go to the home page-http://members@aol.com/TCA/ or Email TCA@aol.com. Its a great investment with quarterly magazines filled with information.

Barrel designations
T-1 Octagon, One line address, flat base, set screw, short site. 6 caliber's T/C Arms Rochester N.H. Caliber (There are variations also) 1967

Pre Type 2, but not Type 1 has the N.H. BUT the caliber is located at the muzzle end

T-2 Octagon, 2 line address, flat base, set screw, significant
identification is a period after the N.H. This type has the largest caliber selection and dates 1967-1972

T-3 Octagon, 2 line address, flat base, set screw, now the period is only after the H. NOT THE N 1973-1975 (bull barrels also found is this vintage)

T-4 Octagon, 2 line address, flat base, set screw is replaced with a roll pin to hold in locking lug. (bull barrels and 14" found in this vintage)

T-5 Octagon or bull the significant change is the flat base that now has a step on it. If you check any of your 14" barrels it will have this step..

Now with in each of the above there are variations that mainly address sites. Sites are another classification in there own right. For those of you shooters out there T-1 - T-4 typically have the solid locking lug, which generally require changing to use on the newer frames, easy open started at serial # 195,000 .

T-6 thru T-9 are current variation that describe hunter barrels, stainless, 16", 21" scope models and so on. Unofficially I have deemed the T-9 indicating the newest rear site as used on the Encore and post-fire Contenders. Once we clearly sort through the 6 thru 8s this may change again. One thing for sure as a collector of TC's, just when you think you have it figured out....something else jumps up and changes every thing.
Good shooting and collecting,