Reading the section about the Walker in Percussion Revolvers A Guide To Their History, Performance, And Use by Cumpston and Bates shows they bought a period correct mold from Dixie Gun Works produced by Pedersoli. It has a single cavity for the 170 grn Pickett bullet. It was the projectile used during the Mexican-American War. They found 45 grns of 3F was the max load. A ball and 60 grns likely became more popular later on the Texas frontier.
Of the 1000 pistols made for the military 109 were returned damaged. Many were claimed lost or damaged but kept according to them.
What’s known as the Dragoon holds 50 grns with a ball.
The Civil War paper cartridges meant for the more common .44’s then made by the Hazard’s powder company held 36 grns of 4F with a 211 grn bullet, and the Johnston & Dow cartridge used 35 grns of powder with a 242 grn bullet.
My Pietta NMA can hold a weighed charge of 38 grns of 3F Olde Eynsford with a ball and still has a little room left.