The Sinclair Bullet Comparator inserts are designed to accurately measure bullet ogive-to-base and loaded round measurements, offering more consistency than overall length methods.
Constructed from stainless steel, these inserts feature a taper and short straight section to closely replicate the chamber throat, reducing wobble during measurement.
These 20 Caliber (.204") inserts are specifically made for use with the Sinclair Bullet Comparator and Bump Gage Body.