Fits Nowlin Tight Bore Barrels
Specially ground, reduced-diameter pilots fit the tighter bore
specifications used on all Nowlin barrels. Will also provide a
satisfactory fit in most other brands of barrels. Each
smooth-cutting, six-flute reamer is precision ground with an
integral throater and solid, fixed pilot.
1911, Issue:09, Page:059
Big Book Catalog, Issue:66, Page:145
New Product Supplement, Issue:515, Page:000
SPECS: M7 high speed steel. Six straight flutes with right hand
cut. 3/8" (6.3mm) square drive shank.