I no longer have my old .45 Colt data that I loaded for my long barreled Ruger Blackhawk .45 Colt/.45 ACP convertible, but I was shooting silhouette competition back in the 70's with that awesome thing and was launching 250 grain jacketed bullets at .44 Mag velocities using full-house W-296 and CCI Mag primers, and all shots would cluster at 25 yards.
That was before such loads were considered routine in that Ruger chambering, and I was in a virtually new frontier. There were very few people that had used these loads before in those guns and there wasn't much of a track record to know what to do. They didn't know at the time that certain slow burning powders were not ignitable at lower charges, and some published loads were giving data that could cause trouble. I had a few memorable and embarrassing experiences before I switched to those primers when the powder didn't ignite and I had a cylinder full of ball powder, and a bullet jammed in the forcing cone, locking up the cylinder. On the other hand, nobody wanted to tell someone to jump in with maximum charges of W-296. Things are much better now, all around, with plenty of established, safe data. As always, such powders call for very close adherence to keeping charges up to maximum, and using hot magnum primers.
But there is no question that the .45 Colt can be very easily made to generate impressive energy, with astounding accuracy. Personally, I always enjoyed the .45 Colt, and found it extremely accurate with such loads, as well as plinking loads. Having had plenty of experience with both the .44 Mag and .45 Colt, my IMPRESSION is that the .44 has a sharper recoil, while the Colt had a more robust, but pushy one, which I found more pleasant in similar framed guns, but that's entirely subjective. Having said that, I always felt in those days that using the .44 Mag was more (if you will excuse the term) legitimate, and that I wasn't in some unknown and adventurous place with the .45. Obviously, that land has been explored fully now, and it's well tread.