After putting up with the cheap hollow range rods for many years, i went to Atwood's and bought one 3/8" x 36" solid brass rod and a solid aluminum rod of the same dimensions. Drilled and tapped one end of the rods for the loading jag.

The aluminum rod is a little soft and it bends a little when leaned on hard. The solid brass rod does not bend.

Total cost of the two rods were less than $10.