Bullet fit input against the normal thinking (45LC)?

[Changeling]

Everything I have read concerning the mechanical/engineering aspect of setting up a revolver for cast projectiles approaches the Revolver measurements from different prospectives concerning the dimensions of the throat and barrel.

Some say the bullet should be 1 thousandth over bore diameter, others (mostly) say place your concern on the cylinder throats and have them 1 thousandth over "throat" diameter.

I'm having a hard time seeing any logic in these measurement suggestions.
If the point of the whole accuracy equation in Revolvers is to keep the bullet as tight to the mechanical line/measurements as possible why in the world would one want to open up a measurement over the bore diameter.

In short if you have a (45 LC) with a bore of .452 why wouldn't you want to keep this measurement from the throat (small increase for insertion) through the entire firing instead of having the throats 1 thousandths or larger in the throat than the barrel ?

[Dale53]

The ideal set up is to have a throat .001" bigger than the barrel groove diameter. If the throat is smaller in diameter than the barrel, the cylinder throats need opened up to .001" larger than groove diameter. If the bullet is sized smaller in the throats, then the bullets will allow gas to excape around them which will lead coat the barrel immediately leading to loss of accuracy.

You can acually get by by having the bullets the same size as the cylinder throats but some like to "make sure" with the bullets .001" larger than cylinder throat size. That can have a negative factor - you may not be able to chamber the bullet...

So, rule of thumb:
Size to the cylinder throats. Bullets somewhat larger than barrel groove diameter will not cause problems as cast bullets are soft enough to conform.

FWIW
Dale53

[Doc Highwall]

The trouble comes from the fact that some revolvers have cylinder throats that are smaller then the bore of the barrel. Also you want to have the boolit seal the cylinder throat preventing hot powder gases from striping the lube and melting the lead as the boolit is leaving the cylinder throat and entering the forcing cone in the barrel.