Sorry sometimes when I try to explain something it comes out clear as mud.
I'll use my Uberti 3rd dragoon as an example. Measuring the diameter of the arbor in the frame that the cylinder rides on. At the tip of the arbor the diameter is .505 at a point just in front of the cyliner the diameter is .530, at the point on the arbor directly above where the frame meets the barrel the diameter is .525. In the arbor hole below the barrel the maximum diameter at the face of the hole is .525. This is the same diameter as the point on the arbor directly above where the frame meets the barrel.
That is as far as the taper will allow the assembly to go without force. If a new shooter, believing that he can adjust his barrel cylinder gap by smacking the wedge does so he ends up sticking the tapers together requiring considerable force to take them apart.
In the machine trades we used the morse taper system to attach tools to the spindle of the machine socking them into place where they stayed until a wedge was run through the spindle behind the tool taper and smacked with a hammer to drive them out.
With the less expensive replicas that use a constant diameter arbor the problems are different as previously stated.
I've seen some new in the box replicas have as much as a .015 barrel cylinder gap. A new shooter, believing that he can adjust this gap down to say .006 with the wedge can do some serious damage to the gun when simply returning it for one better fit or having a machinist shave .009 off the barrel flat at the frame junction would cure it.
It is with these straight arbor guns that it is most important to have the arbor bottom out in the arbor hole in the barrel assembly.
I hope that is a little clearer.
