[gunnysmith]

Rimmed cases such as the 30-30, 7.62 X 54 etc. headspace on the rim, not the shoulder.
Depending upon the brass manufacturer, one is limited to the number of reloads available from such cases.
The problem exists of an annular ring forming near the case head caused by the brass flowing forward due to the pressure created upon firing. The result is a weaking( thinning) of the case in that area.
An annular ring inspection should be performed on each case to be reloaded.
Using a standard metal paper clip, straighten the clip and bend a 15 degree angle into the last 1/8 inch of the clip.
Use the modified clip to reach into the case and drag it up the sidewall.
If there is a ring starting one can feel the forming ring as a hesitation while dragging the clip up the sidewall.
If there is no ring forming the transition will be smooth to the neck.
Any cases which are suspect should be rendered unusable.
Any cases reloaded in such a condition could cause the firearm to be disabled.