Nevada Desert Rat does the Quigley Bucket Shot at 782 yards:
An additional fun fact about straight wall BPCR cases: .45-70 brass can be cut down to make .475 Linebaugh and .480 Ruger casings. Both of these modern revolver cartridges use .45-70 base dimensions as their parent case.
And last but not least, .454 Casull, .460 S&W, .475 LB, .480 Ruger, and .50 S&W can ALL be loaded with a full charge of black powder or BP substitute with a paper or cloth patched round ball or lubed conical hand pressed into it with or without crimping, and still deliver performance almost on par with their factory loadings. If Hodgdons Triple Se7en is used as a propellant, the material is compressable up to 30% of it's original volume and under tension it begins to behave like progressively burning smokeless, producing ballistic performance almost on par with smokeless, yet still generating chamber pressure far below the pressures that the smokeless equivalent would be producing.
ETA: During the legendary Creedmoor long range matches of 1872-1876, some of the American competitors were observed loading their Sharps or Remington Rolling Blocks in a peculiar fashion. Instead of inserting a loaded cartridge into the breech of their rifles, they would insert a primed and powder charged case, close the breech, and then load the bullet down the bore like a muzzleloader, using a ramrod to drive the projectile home before then taking position, cocking, and firing. It was later revealed that loading slightly oversized bullets in this fashion produced a bullet that already had the rifling imprinted on them and these produced even more accurate flight once shot.