Redding dies leaving circular rings on brass?

[Roughrice]

I recently had this happen with a RCBS die after calling RCBS they said the die did not get totally polished inside, they sent me a new die and problem was solved,those rings are not so much scratches as chatter marks from the die, try a different die and see if your problem is solved

In my limited experience with machining...If the die had circular grooves from the reamer... the vertical force of drag while running a case up a sizing die would leave vertical not horizontal striations although the groove is circular. In fact, the only horizontal ring mark that would be left would be at the top of the stroke where the grooving will stop... at which point it is no longer creating sizing force.
Does that make any sense?
I mean... in the case of the die being grooved, that's how the die can create circular patterns on brass like it does at the case head (end of stroke).

 

[bigngreen]

It's not the die it is just that the dies is ironing out the cases and anything slightly transfered from your chamber OR like Lance said riding in a case.
Any die issues show up in lengthwise marks or shoulder dents.

 

[Roughrice]

It's not the die it is just that the dies is ironing out the cases and anything slightly transfered from your chamber OR like Lance said riding in a case.
Any die issues show up in lengthwise marks or shoulder dents.

That is my line of thinking as well. Just wandering how the RCBS die replacement actually stopped "ringing" JKB57's brass.

 

[bigngreen]

That is my line of thinking as well. Just wandering how the RCBS die replacement actually stopped "ringing" JKB57's brass.

Ya, reread it and if the case is popping into the die it could leave chatter marks like what someone else said. It would be interesting to see how much sizing is going on, the only times I've gotten a chatter feel to sizing was either a lube issue which case puller came out shortly, or doing some aggressive sizing.

 

[Mike Matteson]

Perhaps the die is not at fault but the brass? It appears from the photo that you have raised ribs on the brass and as the brass is pushed into the die it polishes the high spots on the brass. Can you feel the rings on the brass? Take a straight edge and put on the brass with a back light and see if the rings are higher that the body of the brass? If the die had rings in it you would have difficultly getting the brass back out of the die after sizing. I would simply shoot and stop worrying. If it bothers you just tumble them in some polishing media.

Problems with that is the cases are tapered, so pulling the case back out of the die, I feel doesn't ring true. Clean the dies, then see what it looks like.

 

[lancetkenyon]

Use more lube. Or better lube.

 

[Stonyman88]

300 WBY Brass that was previously neck sized. Shot, and now I'm trying to full length resize. I'm using sizing wax and tried hornady case lube, but I'm getting circular scratches going around the case. I removed the decapping pin and mouth sizer ball assembly, and it was still doing it, so its for sure the die body. Any one else ever see this issue?

I only use Imperial , and have you tried a brand new case to see if it happens a never fired one? If it's in the die, polish it or send it back for replacement

 

[milo-2]

I say those are stretch marks from your brass growing excessively in your chamber. Take some measurements from new brass to this stage. See how much it is growing in length.

 

[ken158]

I would think you would have directional striations on the brass going into and out of a die but your marks appear to be chamber marks.