I do believe the author is referring to the Pyrodex pellet charges of 20, 40 60 gr that can be had instead of loose powder, and they work, but are much more expensive than loose powders.You must further edify us. What do you deem a "pellet"?
The word is sometimes used to describe shot inside a shotgun cartridge. It is frequently used to describe a hollow base wasp wasted lead projectile in airguns.
In loading black powder cap and ball revolvers, the ball is just that, usually a .454" or . 457" pure lead ball. Conicals, pointed pure lead bullets may also be used. Those with a slightly rounded or beveled base edge will load best. Balls slightly larger than the chamber mouths such the when loaded a very thin circle of lead is sheared off are best.
And will a 45 pellet work in my soon to be delivered 44 Colt Walker?
Pyrodex 44 caliber pistol pellets are designed for 44 caliber revolvers but seem to come in 30 grain only. The Walker can take up to 60 grains of loose with a round ball.
The Walker like all 44’s is actually a 45 caliber handgun. A 454 round ball and even a 457.
For those that use the 45/50 pellets are they the same diameter as the 45 Pryodex. ?
The 30 grain pistol pellets are advertised as fitting .44 - .45 cap & ball revolvers.
The .44-caliber pistol pellets are approximately .40 inch in diameter and .63 inch in length.
When fired in an EMF Remington 8" revolver with a round ball, it produced a velocity of 862 FPS, with a variation of 72 FPS, and a group of 3.13". --->>> https://www.shootingtimes.com/editorial/ammunition_hodgdon_0728/100508
A couple of posts indicated that other Uberti models have chambers that measure .444 [1860] and .445 [1858].
Mykeal indicated that his 2007 Uberti Walker had a chamber diameter measuring .449. --->>> https://www.muzzleloadingforum.com/threads/uberti-walker-diameter-load.53236/#:~:text=58 Cal.&text=My 2007 Uberti Walker has,449 diameter chamber mouths with .
Whether the .45/50 pellets are a tight fit in the Walker chambers or not, their diameter should be able to be slightly adjusted by hand if necessary.
They need to be small enough to be able to fit into a .45 bore.