Darkerx this is how a wedge is to be used.
Darkerx,
The original Colt's pattern designs had the arbor hole in the barrel underlug cut to a depth that caused the arbor to bottom out in the hole. This is what set the cylinder gap, not using the wedge as an adjustment feature. Armi San Marco and Pietta usually have arbors of correct length, Ubertis almost always have an arbor that is too short. Uberti is taking manufacturing shortcuts to reduce costs and we have to come along behind them and correct them. Those of us that have been shooting Ubertis for a long time have different methods of correcting this condition.
Let me direct you to Pettifogger's excellent series that was published in the
Cowboy Chronicle It is archived over on
The Open Range, these are the two articles of interest.
http://www.theopenrange.net/articles/Tuning_the_Uberti_Open_Top_Revolvers_Part_3.pdf
http://www.theopenrange.net/articles/Tuning_the_Uberti_Open_Top_Revolvers_Part_4.pdf
The first two installments are also excellent as well as his write up on gunsmithing the Pietta Colt's reproductions.
I have three original Colt's revolvers and I can attest to the fact the arbors all bottom out in the barrel underlug. The wedge was intended to be simply a "locking" mechanism, no more.
I basically do the same thing Pettifogger does on my revolvers but I use a threaded button and try to match it to the arbor. I have the resources to do that and I am a bit anal, but I think Larson's solution is simple, inexpensive and meets the needs of 99.9% of the shooters.
I have some pictures somewhere, but you can barely tell that the button is even there, so I will direct you to some CAD models of the spacing button I use.
http://www.cascity.com/forumhall/index.php/topic,36113.msg462569.html#msg462569
http://www.cascity.com/forumhall/index.php/topic,36113.msg462482.html#msg462482
Two of my originals are well preserved original 1860s and I spent some time with them determining what the original intent had been for the design. One Pistol built in 1861 has a .009" cylinder gap, I have another produced in 1862 which is in even better shape and it has a gap which is probably .0105". A .010" feeler gage will go and a .011" will just start. I did some additional research and consulted with other 1860 owners and found their original pistols ran between .008" and .012". I have a Colt's shop manual for SAAs and they specify a .008" gap for the Generation 2 and later revolvers (that's using smokeless powder). There is also a reference in a copy of another shop manual I got from one of my former instructors who worked at Colt's for 40 years that the Gen 1 revolvers cylinder gap go/no-go gage was originally .008" to .010".
I finally "relearned" what they knew 164 years ago, a Colt's pattern revolver works best with a cylinder gap of about .008"-.010" for a cap gun and .006" -.008" for a cartridge revolver with a gas ring to control the end shake.
If you have any questions, just ask.
Regards,
Mako