Can't comment on the TB load, but your light to medium load with a 260 gr bullet and 7.8 gr. of Unique has been the go to load for .45 Colts for longer than I"ve been around (70 yo now). My own cast bullets come out 6-8 grains heavier than that and they work fine through all 3 of my .45's (two Rugers and a Gen 3 Colt SAA). My guns will put that combination into 2" gps at 25 yds all day long. I size mine to 0.453"-0.454" and get superb accuracy.
Just a heads up on Rugers. Some have small cylinder throats i.e. 0.450-0.451" and will not shoot lead alloy bullets with any great accuracy and usually with considerable leading in the barrel leade. The cure is to have them reamed out to a uniform 0.4525". I did it with both of mine (around $60 each) and it cut my groups in half. Jacketed bullets are not as picky as to throat diameter and you may have better luck with them.
HTH's Rod
Just a heads up on Rugers. Some have small cylinder throats i.e. 0.450-0.451" and will not shoot lead alloy bullets with any great accuracy and usually with considerable leading in the barrel leade. The cure is to have them reamed out to a uniform 0.4525". I did it with both of mine (around $60 each) and it cut my groups in half. Jacketed bullets are not as picky as to throat diameter and you may have better luck with them.
HTH's Rod
