The bench guns were being built before the Civil War, but afterwards, in the 1870s and 1880s, they became an artform, as even then, people wanted to keep alive Black Powder Muzzle Loading Rifle Shooting as a sport. Harry Pope made barrels first for MLs, and then for breechloaders, but kept the use of the false muzzle, and the muzzle seating concept, arguing that it produced the best accuracy at long ranges, compared to the Breech loaders. To prevent distortion of the bottom of the bullets, the first breechloading target guns used " bullet seaters" and paper patched bullets in front of casings containing black powder, and later smokeless powder( semi-smokeless powder) held in the casing with a card wad.
I like to think that those first men, both here and in Europe, who tried to make a better, more accurate rifle for long range shooting. showed the way to all that have followed, teaching us the importance of keeping the base of a bullet square to the bore, so that the development of higher speed bullets and smokeless powder lead logically to the use of harder, copper jackets around a lead core to give us the guns, and accuracy that men of those days could only dream about. The fact that men in our lifetime are making killing shots on enemy combatants at more than a mile would make all those men smile.