Re: Why 6 lands and grooves

First of all the barrel diameter is bored and honed to a diameter
<br>of .445 inch..
<br>A rifling tool based up on the rifling tool made by Salmon River
<br>Slim.&nbsp; It is in effect a dual cone in which the outer cone is
indexed
<br>so it cannot be rotated independent of the shaft, by mounting the cone
<br>on beveled splines that allows the cone some independent forward and
<br>backward motion.
<br>This cone head, has leaves that mount the cutting surfaces which are
<br>cut on the bias conforming to the twist of the thread cutting mechanism
<br>of the lathe.&nbsp;&nbsp; As the lathe forces the dual cone through
the barrel from the
<br>chamber to the muzzle, the inner cone which is a large angle than the
outer
<br>cone forces the leaves of the outer cone out, to cut away the metal
to form
<br>the grooves.&nbsp;&nbsp; When the cutting cone is reversed the inner
cone with draws
<br>from the outer cone allowing the leaves of the outer cone to retract
under
<br>spring pressure as the&nbsp; motion is reversed.&nbsp;&nbsp; The&nbsp;
threading mechanism on the
<br>lathe creates the turn ratio, and the cone leaves cut the grooves.
<p>The cutting cone will make multiple passes until the diameter of&nbsp;
barrel from
<br>groove to grove is .451 inch.&nbsp; This will create riflings that
are .003 high.
<p>The cutting cone does not leave the barrel so when the cone is with
<br>drawn back through the barrel to the chamber the pressure on the
<br>cone leaves is reduced so their is little cutting.&nbsp; When the cone
is
<br>forced back through the barrel from the chamber to muzzle the
<br>pressure of the inner cone forces the leaves out to cut away the
<br>material to make the grooves.
<p>At least that is how the rifling mechanism worked that Salmon River
<br>Slim used to make his home made flint lock rifles way up on the
<br>Salmon River.
<br>&nbsp;
<p>The Independent
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