The 1848 and 1849 were made in a single combined serial number range, and the transition form one pattern to the other is a bit hazy. The first pattern had a square-backed trigger guard, round cylinder stop notches, and an “Indian Fight” cylinder scene. They were made without loading levers, and with 5-shot cylinders. The second model moved to a round-backed trigger guard and “Stagecoach” cylinder scene, added a loading lever, but retained the round cylinder stop notches. This was shortly followed by the third pattern with square cylinder stop notches. That third model would account for the vest majority of production.
Overall, about 340,000 Pocket model revolvers were made by Colt, including about 11,000 made at the London armory between 1853 and 1856. Production in the US ended in 1873, when Colt transitioned to self-contained cartridges instead of percussion designs.
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