Howdy
Been loading 45 Colt with Black Powder for over ten years in CAS now.
No experience with 45 Colt in a rifle, all my lever guns are chambered for either 44-40 or 38-40.
But I fired BP loaded 45 Colt in my 'original model' Vaqueros for many years before a pair of 2nd Gen Colts became my main match pistols. I can see no difference whatsoever in how the Vaqueros handle Black Powder than how a Colt handles it.
Just for the heck of it, the three cylinders in this photo are, left to right, 2nd Gen Colt SAA, 45 Colt; Ruger New Vaquero, 357 Mag; and Uberti Cattleman, 45 Colt. The photo was actually taken for a comparison of the bevels on the front of the cylinders, but should give a rough idea of the comparative sizes of the bushings.
I suspect shooting Black Powder through a New Vaquero would not present any problems, fouling wise.
I agree with the other posters. Wads and cookies and all that jazz are a waste of effort with 45 Colt (45 Schofield, 44-40, 44 Russian, and 38-40 too) Just put in enough Black Powder so that when the bullet is seated the powder will be compressed between 1/16" and 1/8". That's all there is to it.
However choice of bullet style and choice of lube is very important. Years ago I went through the whole business of melting modern Smokeless lube out of modern Smokeless bullets and pan lubing them with a mixture of about 50/50 beeswax and Crisco. My experience showed that a typical hard cast bullet cannot hold enough soft BP compatible lube to keep the bore of a rifle coated with lube for its entire length. The bullets were fine for a revolver, but a rifle barrel would get starved for lube about the last 6" near the muzzle. This resulted in hard fouling being deposited which caused a lack of accuracy. Easily remedied with a little swabbing with water based BP solvent, but it was a bit of an annoyance.
After I discovered the Big Lube bullet series there was no going back. Nothing but Big Lube bullets lubed with SPG for me anymore. For 45 Colt there is the PRS 250 grain bullet and a little number I designed myself called the J/P 45-200, weighing in at 200 grains. Dick Dastardly redesigned it a little bit and it is now 210 grains. For 44-40 I only use the 200 grain Mav Dutchman bullet and for 38-40 the 190 grain 38-40 bullet.
My standard load for 45 Colt is the PRS 250 grain bullet with 2.2CC of FFg powder. I hesitate to call out the exact weight of powder because different brands weigh different amounts. I like to use Schuetzen powder, it uses a better grade of charcoal than Goex and leaves less fouling behind. The powder Graf's sells is the exact same powder, packed in Graf's bottles. I have never tried the premier powder, Swiss, because it is too expensive. As a round figure, my 2.2CC load of Schuetzen FFg is somewhere around 33.5 grains.
One word - because the J/P 210 bullet takes up less space in the case, following the prescription of 1/16" to 1/8" compression, the amount of powder under the 210 grain bullet will be more than the amount under the 250 grain bullet.
I have not bothered with fillers for quite a long time, too much bother. But I do know it is not necessary to separate the filler from the powder with a card. Once compressed, they will not mix.