I have a new service 455 that was converted to 45ACP back in the day. I did not like to fool with the moon clips plus it was very inaccurate, which since the bore was near perfect I that I thought might be due in some part to the difference in bullet diameter. In any event I Bought a cylinder , from Mr Dunn on the board, and took it the the Smith. When checking things the cylinder is 4 thousands to long. Sooo ! we can trim the cylinder on the forcing cone end or trim the forcing cone. we decided to trim the cylinder. Was there this much variation back when this was made(1914) that there would be this much variation??
New Service 455 cylinder reconversion
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Was the replacement Cylinder you got an original .455?
What does ".004 too long" mean in this context - that with no Cylinder to Forcing Cone 'gap', it was .004 too long? Or, that it did not allow enough gap? Or..?
Just trying to understand here...
Far as whether New Service Cylinders wandered up or down enough for one to speculate on there having been a + or - tolerance of .002 ( or more ), I don't know...but given the relationship of Cylinder to threaded portion of Barrel, and also that of the threaded portion of the Frame, where, either all three had to be held pretty well to 'right on', and then would STILL probably tend to need 'fitting', or, all three were allowed to wander a little, and if the latter, it would allow the final fitter to elect compatible Parts ( from Bins of plus, zero, and minus or whatever ) when assembling, and, save some troubles that way on not having had to hold these three parts too close in their tolerances when being made...or, in other words, in my imagination anyway, "could be" ( that the length of the Cylinders wandered a little up or down from some mean, just as I would expect the Threaded portions of the Frame and Barrels to have done, but I would not expect much more of a spread than say .004 if just trying to imagine it...which is to say, plus or minus .002 is a reasonable Goal for machining repetitive Parts of those kinds with the Tooling of the day).
What does ".004 too long" mean in this context - that with no Cylinder to Forcing Cone 'gap', it was .004 too long? Or, that it did not allow enough gap? Or..?
Just trying to understand here...
Far as whether New Service Cylinders wandered up or down enough for one to speculate on there having been a + or - tolerance of .002 ( or more ), I don't know...but given the relationship of Cylinder to threaded portion of Barrel, and also that of the threaded portion of the Frame, where, either all three had to be held pretty well to 'right on', and then would STILL probably tend to need 'fitting', or, all three were allowed to wander a little, and if the latter, it would allow the final fitter to elect compatible Parts ( from Bins of plus, zero, and minus or whatever ) when assembling, and, save some troubles that way on not having had to hold these three parts too close in their tolerances when being made...or, in other words, in my imagination anyway, "could be" ( that the length of the Cylinders wandered a little up or down from some mean, just as I would expect the Threaded portions of the Frame and Barrels to have done, but I would not expect much more of a spread than say .004 if just trying to imagine it...which is to say, plus or minus .002 is a reasonable Goal for machining repetitive Parts of those kinds with the Tooling of the day).
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