Articap,
That’s okay, we have all of Colt’s patents and the one you are talking about was his second dated August 29, 1839.
That’s’ true Colt did make a claim concerning chamfered chambers in his “Improvements” patent, but as Paul Harvey says, now for the rest of the story…
First let’s look at the claims and illustrations that are part of the patent.
What Colt is describing is not the little chamfer that Kwhi43 shows or like any edge break I have ever seen anyone attempt on a modern reproduction. The chamfer would have to be very large to even attempt to do what the claim proposes. Note how that the chamfer is literally as large as the forcing cone opening on the barrel. Below is the claim.
What most people don’t know is that early Colt pistols had major problems with chain firing. Colt had been trying to sell his revolvers to the United States government, but during a trial he had a chainfire and two chambers fired, it ruined his chances for a contract. His major problem was his enclosed breech face and in some cases the enclosed front of the cylinder face of his rifle designs. He actually tried to encapsulate it. Colt had been pushing the “water proof” qualities of his design much to the detriment of safe shooting. On his reissue patent of October 24, 1848 he removed the sections concerning the covered areas. Otherwise the patent which was called the Reissue patent #124 was just the same as his original patent issued as #138 February 25, 1836. His claims for the chainfire reducing and redirection capability of the chamfers were not borne out by testing, it was an attempt to get around the Leavitt patent and was the first of years of competition and confrontation between Colt and Leavitt.
A Smithsonian firearms historian in 1966 spoke of the Colt failure in his government trials and how he used the Daniel Leavitt patent of April 29, 1837 as a reference in documents to the government in an attempt to get a second trial. His patent was an attempt to address the problem. Unfortunately for Colt he went out of business before he could get a second trial. The reality of the chainfire problem is the exact problem we have today. It was his closed breech that was causing his problem. In fact the chamfers caused increased flash and gas release at the barrel to cylinder interface. This was a phenomenon also present with the Leavitt convex cylinder face which directed the firing gases escaping the gap up and out from the cylinder gap.
Colt abandoned or didn’t put his chamfers on his production rifles, shotguns and pistols. There was no actual advantage and the revolving pistols, rifles and shotguns produced from 1839 to 1842 (1847 for Ehlkers) don’t have the chamfers as shown in the 1839 patent incorporating the chamfer “improvement.” By the time he re-entered business with the Walker revolver it was obvious had realized that redirecting gases at the breech end had solved the majority of his problems and his later patent illustrations and manufacturing documents never made mention of his claims for chamfered chambers in 1839. He submitted a request for patent reissue on his original 1836 patent and was granted that in October of 1848, but he made no attempt to extend or get a reissue of his “improvements” in the patent #1,304 of 1839.
So that is the rest of the story...
You never hear about his failure with the trials or the major problem with Paterson chainfires. Not all of Colt’s ideas or granted patent claims were desirable or even good ideas. It’s too bad the tooling room and pattern shops were destroyed in the fire of 1864, it would be a treasure trove of models that didn’t work out and what “almost was…”
Later in his career with Colt’s he will be involved in several lawsuits with Leavitt and Leavitt& Wesson.
Regards,
Mako
