Sinclair International .220 Swift 21 deg Shoulder Bump Gauge Insert

Bump Gage Features Sinclair Bump Gage Inserts are used to measure the amount of shoulder bump when setting up full length sizing dies. Our Bump Gages install in either of our comparator bodies and are machined to fit particular shoulder angles of cartridges. Rather than measuring to the datum line these gages 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. We 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. Bump Gage Specifications Sinclair International Bump Gage Insert 220 Swift