The answer is it depends.

1st generation colt barrel thread is .695-20tpi tapered
2nd generation barrel specs were the same as 1st
3rd generation thread is 24tpi
Uberti thread is 11/16-20tpi which is smaller than colt
Pietta thread is mertic 18x1

Whatever you have might be different, and your gunsmith should be able to figure it out.