Our Swage Rod Backer is made from S-7 tool steel, then through hardened, not case hardened. We've removed the expansion lip, and properly profiled the tip so as to not snag on case necks.
This swage backing rod has a stem diameter of 0.300" and is designed specifically for use with 9mm and larger shell cases, including 7.62x51, .300 Blackout, and .45 ACP.
As of 1/3/2018, we lengthened our large expanders for hold down of longer cases such as 30-06.
Required but not included:
Dillon Swage Backup Die Body p/n 12184
Dillon 9/16x18 Lock nut p/n 13483