tailstock offset

One method of cutting the tapers needed to contour rifle barrels is to offset the tailstock of the lathe.

The math looks like this:

TPI=TPF/12

TPI=(D-d)/TL

TSO=(OL/TL)*((D-d)/2)

TSO=(OL/TL)*((D-d)/2)

Where:

  • TPI=threads per inch
  • TPF=threads per foot
  • D=taper’s large diameter
  • d=taper’s small diameter
  • TL=taper’s length
  • OL=barrel’s overall length

All length measurements are in inches.