skydve76:
Your post didn't provide a picture. Nevertheless, the "bright ring forming down by the rim" is potentially a matter of serious concern to reloaders.
One cause for that bright ring is excessive headspace.
On firing, pressure inside the cartridge case forces (clamps) the cartridge case firmly against the inside of the chamber, holding the front end of the case tightly in place.
If there's excessive headspace, then the head of the cartridge moves backwards, stretching the brass in the case, making it very thin at the bottom of the cartridge case down by the rim.
Evidence of this condition is usually in the form of a bright ring around the case, near the rim.
The case is very thin at that point AND MAY BLOW VIOLENTLY. Which you do not want.
SUGGESTION:
In the interests of your safety, be willing to sacrifice one case. Cut it lengthwise with a bandsaw or a hacksaw. Look for thinning in the wall section near the bright ring.
If thinning is found, DO NOT fire a round which evidences the bright ring. It's a KA-BOOM waiting to happen.
sfg