At this point, I attribute the misfires (I think there were two out of 30 rounds in the match) to an EXTREMELY hour-glassed mainspring. 

  Well Heck 

Just a tiny little point here.  Nearly as I can remember from my spotty research, Colt didn't convert the 1861 percussion guns to cartridge.  The Navy only had 1851 Navy guns, of which they (the Navy) did send a pile to Colt for conversion.

This was the basis for my only (other than no quality control) criticism of the late Armi San Marco "1860" Richards conversions.  Those guns were ALL based on the 1861 which Colt did not convert.  Although I still think the Armi San Marco conversions were the best looking "modern" conversions even if historically incorrect.

Colt converted both '51 and '61 percussion guns, but only as Richards-Masons.  Never converted either of them to Richards type 1 or type 2 (well, they made ONE type 2 '61 that is shown in McDowell's book, which is what I use as the basis for my type 2 '61  ).

The '61 R-M barrels were sleeker than the percussion barrels, had the bottom trimmed off.  No modern manufacturer has ever reproduced that one.

I know you guys already know this, but Hi-Tec coatings do absolutely nothing for Black Powder shooters.  Shooting BP you gotta have enough BP compatible lube.  Hi-Tec is acceptable though, iff your shooting APP.

   Well Heck 

Just a tiny little point here.  Nearly as I can remember from my spotty research, Colt didn't convert the 1861 percussion guns to cartridge.  The Navy only had 1851 Navy guns, of which they (the Navy) did send a pile to Colt for conversion.

This was the basis for my only (other than no quality control) criticism of the late Armi San Marco "1860" Richards conversions.  Those guns were ALL based on the 1861 which Colt did not convert.  Although I still think the Armi San Marco conversions were the best looking "modern" conversions even if historically incorrect.

Until you said wood grips, I was going to suggest http://www.gripmaker.com/ and https://gungrip.com  for faux ivory grips.  The latter is N C Ordnance, and they say theirs is for a Beretta Stampede Bisley which I've never even heard of but probably made by Uberti.

I saw them too in my search.  The Stampede is an early gun and probably has a two piece grip frame. All Bisley's coming out of Italy now by Uberti have a one piece grip frame.  Stocks for one will not fit the other, from what I have learned.