Howdy Again
The problem was the Rollin White patent which Smith & Wesson controlled since 1857 when they founded their new revolver company.
Rollin White was a former Colt employee. He had a brilliant idea one day. Self contained metallic cartridges were just being developed around the middle of the 19th Century. White's idea was to make a revolver with holes bored straight through the cylinder so that metallic cartridges could be loaded into them. Do away with the entire idea of the Cap & Ball cylinder with nipples and percussion caps. White cobbled together a prototype to present his idea to Sam Colt. I believe he used a Dragoon. In what was probably the worst business decision of his entire life, Colt rejected the idea. So White patented it himself. Simple idea. Bore straight holes directly through the chamber so that cartridges could be loaded from the rear. Change the hammer design to include a firing pin.
When S&W founded their new company in 1857 to make revolvers, they had the same idea. Bore holes through the chambers to allow it to accept cartridges. Their first design was a little 22 caliber revolver that chambered a 22 RF round that had just been developed by a Frenchman named Flobert. But when they did a patent search, S&W found out that White already held a patent on their idea. They could not legally make such a revolver without infringing on his patent. At first they attempted to buy the patent outright, but White would not sell. Instead, they struck a deal where White licensed S&W to build revolvers using his patented idea, and they paid him a royalty of 50 cents on each revolver produced. This arrangement remained in effect until the White patent expired in 1869 or 1870.
Until that time, anybody in this country who attempted to produce a revolver that used a bored through cylinder to accept cartridges was in violation of the patent, and S&W were fierce about enforcing it. Actually, part of the deal they struck with White was that he had to police the patent violations. He eventually died penniless from spending all his money on hiring lawyers to chase down all the patent infringements. And their were plenty.
S&W did allow Remington to convert some of the 1858 Army percussion revolvers to cartridges, but that was a licensed deal and Remington had to pay a royalty to S&W for every revolver converted.
Colt wound up kicking himself around the block for not seeing the handwriting on the wall about the coming of cartridges and how they would change the entire firearms industry. But his hands were tied, there was nothing he could do about it until the White patent expired. Colt died in 1862, long before the White patent expired. The Colt company did come up with the Thuer conversion for the 1860 Army in 1869. It used a special reverse tapered cartridge in an effort to get past the White patent on straight bored chambers. But the Thuer conversion was not very successful.
When the White patent expired in 1869 or 1870 (I have seen both dates stated), the flood gates were opened for everybody to begin making revolvers that would accept cartridges. But Colt had been asleep at the switch and did not have a new revolver ready that was specifically designed to take cartridges. So the Richards Conversions and the Richards - Mason Conversions were stop gap measures to start selling cartridge guns until they came up with a new gun specifically designed for cartridges. The Open Top was designed specifically to load cartridges, but it was really an adaptation of the earlier 1851 Navy design. Colt submitted it to the Army for approval, but the Army had decided it would only accept designs of cartridge revolvers with solid frames. So the Open Top was rejected.
Finally, in 1873, three or four years after the White patent expired, Colt brought out the SAA.
S&W had not been sitting on their hands all the time they held the monopoly on producing cartridge guns. They knew when the White patent expired there would be stiff competition for revolver sales. So they unveiled their new large frame 44 cartridge revolver that eventually became known as the American revolver in 1870. This was their first Top Break revolver. The Top Breaks featured a new mechanism that automatically ejected spent cartridges when it was opened. They then went through their entire line of revolvers, creating Top Breaks in 32 and 38 calibers. The S&W American revolver eventually gave rise to the Russian, Schofield, and New Model Number Three, which all had the automatic ejection feature.