I've never had a problem with the clearance I have on the Dragoons ( .0015"). I set all my customers open tops B/C clearances at .0025" as well and many are CASS/ SASS shooters. Never have had a report of "heat" lock up. Maybe the cylinders in the Dragoons are big enough to absorb the heat? Likewise, the bp cylinders of the open tops? I got my numbers from Freedom Arms and Mag.Research years ago when I was researching my tolerances for my service. I have set up some as fanners (and are used that way) with no ill effects as well. A tight clearance increases efficiency (measurable or not) and much less wear (open tops) and since most everything is going out the barrel, a much cleaner, longer running revolver is the result. Typical is 160/180 rounds from an open top with no binding (bp). Of course the cartridge set ups are as reliable as any fine modern S.A.
Mike
www.goonsgunworks.com
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