Skip to content

Sinclair #40 40° Bump Gauge Insert, (Up to 6MM) Ackley Improved 40°

SKU SIN-749011482

Notify me when back in stock

Sinclair Bump Gage Inserts are used to measure the amount of shoulder bump when setting up full length sizing dies. These Bump Gauges install in either of the Sinclair or Hornady comparator bodies and are machined to fit particular shoulder angles of cartridges. Rather than measuring to the datum line, these gauges indicate off of the shoulder of the case to get a better, more easily assessable measurement of how much you are actually sizing your cases.

Sinclair usually recommend between .001" to .002" bump for bolt action rifles and between .003" and .005" for AR-15 type rifles. Also, a useful tool for keeping your brass and loaded ammunition separated if you have multiple rifles chambered for the same cartridge and checking loaded ammunition.

Suitable for the following Cartridges:

243 Winchester Ackley Improved 40°
220 Ackley Improved 40°
6MM Ackley Improved 40°
22-250 Ackley Improved 40°
22-6MM Remington Ackley Improved 40°
223 Ackley Improved 40°
6MM/30-30 Ackley Improved 40°
22/30-30 Ackley Improved 40°
228 Ackley Magnum 40°