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Sinclair stainless steel neck turning and expander mandrels
for 17 through 50 caliber cartridges are turned from high
grade stainless steel on precision turning centers. Turning
mandrels are sized .002" under bullet diameter and
expander mandrels are .001" under bullet diameter. The
shape and surface of all of our mandrels is the result of years of
experimenting by many expert handloaders. Our Carbide turning mandrels
are precision ground from solid carbide stock, which yields even closer tolerances. All
Carbide mandrels are ground to .002" under bullet diameter. Adjustments on our NT-4000
turning tool will be more consistent with
carbide mandrels due to the tighter tolerances
of the mandrels. Large caliber (35
to 50 caliber) mandrels fit only the Large
Caliber Expander Body and the NT-5000 Turning Tool