What's up with this .357 sizing die?

Poper

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Check this out.
I was setting up my RockChucker to load some .38 Special. I dug out the RCBS carbide die set and this is what the sizing die looks like.
You can see the steel of the die body has peened itself into a thin foil overlapping the carbide insert. This is a first for me. I wonder if RCBS will warranty this?
357 die.jpg
 
Someone seriously cammed over something! Wow
No, not really. If over camming was the cause, I would think it more likely to have crushed the shell holder or cracked the carbide insert, but has done neither.
The carbide insert is actually slightly recessed into the body and steel of the machined surface of the bottom of the die has peened over the carbide over the years. I just noticed it tonight. There have been several thousands of rounds loaded with this die over the last 30-35 years.
Notice the peened area is not uniform around the surface as though something is not perfectly square and true with the world. None of my other dies are wearing like this and I have loaded more .308, .270 and 6.5x55 than I have .38 Special/.357 Magnum.
 
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Check this out.
I was setting up my RockChucker to load some .38 Special. I dug out the RCBS carbide die set and this is what the sizing die looks like.
You can see the steel of the die body has peened itself into a thin foil overlapping the carbide insert. This is a first for me. I wonder if RCBS will warranty this?
View attachment 1265623

Impact nothing in the operation of the die. The carbide insert is recess so it does not get damaged. Normal. If it was flush it could have cracked the carbide.
 
Impact nothing in the operation of the die. The carbide insert is recess so it does not get damaged. Normal. If it was flush it could have cracked the carbide.
Agreed. However, note that the wear is inconsistent around the die opening which implies something is out of square. The die, press and shell holder are ALL RCBS products. I suspect the die to be the issue. BTW, the die is properly adjusted with light cam-over without a case in the die.
 
Following instructions provided by the manufacturer when setting up dies matters. Mine says to raise platform, screw dies in until touches shellplate, then back off 1/4 turn.
If you back off that 1/4 turn, or even 1/8 turn, this will never happen unless the platform got canted somehow which is unlikely. But, your die still very well might work just fine with no issues.
 
Maybe send RCBS that picture with explanation and see what they say. Can't hurt.
The last three times I have contacted RCBS via email in regards to product issues, I have not received replies. All within the last 18 months.
I plan to try calling them Monday.

ETA: from the RCBS instructions -
SIZING WITH CARBIDE SIZER DIES Screw the Sizer Die into the press until the die touches the top of the Shell Holder when the Shell Holder is brought up to the top of the press stroke. Tighten the die Lock Ring. DO NOT CAM OVER on a carbide sizing die! CARBIDE SIZER DIE A Tungsten Carbide Sizer Die will give you a lifetime of perfect service if properly cared for. However, the die will not withstand severe impact such as dropping. The Shell Holder should never strike the bottom of the die. When using a Carbide Sizer Die, it is not necessary to lubricate a straight-wall pistol case. However, the .30 M-1 Carbine is heavywalled, tapered, and must have some lubrication. The .500 S&W and .460 S&W need occasional lubrication as well. We recommend lightly lubricating every fourth or fifth case for best results. Screw the die into the press until it just touches the Shell Holder. DO NOT CAM OVER.
I still wonder at the uneven wear, however. It is adjusted for a slight cam-over of less than 1/16 turn (just to eliminate play). I will readjust to just touching per the RCBS directions.
 
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i have always called RCBS and have done the call back optipn. They have always called right back promptly.
Any issue I have ever had they took care of it with out ever any charge and i recived the part with in day of the phone call.
RCBS has the very best customer service.
They recieve phone calls Monday thru Thursday.
No call on Fridays.
 
Check this out.
I was setting up my RockChucker to load some .38 Special. I dug out the RCBS carbide die set and this is what the sizing die looks like.
You can see the steel of the die body has peened itself into a thin foil overlapping the carbide insert. This is a first for me. I wonder if RCBS will warranty this?
View attachment 1265623
Send it BACK!!! let’s see if the will hook it up!!!
 
New 2023 production are different then old 1970s carbide dies.
Both of these 357 mag dies are from around 2023.
One is a RCBS free replacement.
The other came in a set. Bought the new set because they now come with an M type expander.
Both dies are new type RCBS in photo.

20250517_113215.jpg
 
what is an M expander
M die is a different flare to the case mouth, on newer RCBS dies. The bullet will sit straighter on the case mouth. Better alignment.

Lyman made the original M die way back in the late 60s, when i started reloading. Made for lead cast bullets, so lead is not shaved off on seating.
Photo of my RCBS 9mm M die.

RCBS9MM2021 M TYPE..JPG
 
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M die is a different flare to the case mouth, on newer RCBS dies. The bullet will sit straighter on the case mouth. Better alignment.
Lyman made the original and called it their "M-die"...that's why it is commonly referred to as a M-die profile expander.

This has been adopted by Redding and RCBS (after the patent expired?) and was recently adopted by Lee for their powder-through inserts.

The big difference is that it doesn't "flare" the case mouth (like a trumpet), but forms a "cup" with parallel sides to hole the bullet in alignment with the case as it enters the seating die. This is especially beneficial when loading on progressive presses as the cases travel between die stations...when using a bullet feeding die
 
The last three times I have contacted RCBS via email in regards to product issues, I have not received replies. All within the last 18 months.
I plan to try calling them Monday.

ETA: from the RCBS instructions -

I still wonder at the uneven wear, however. It is adjusted for a slight cam-over of less than 1/16 turn (just to eliminate play). I will readjust to just touching per the RCBS directions.
RCBS we knew doesn't exist anymore. Gone are the days of Huntington's quality and customer service. Bean Counters are running it as part of a conglomeration of other businesses. You now matter far less to RCBS.
 
RCBS we knew doesn't exist anymore. Gone are the days of Huntington's quality and customer service. Bean Counters are running it as part of a conglomeration of other businesses. You now matter far less to RCBS.
I recall hearing this awhile back. I will give them a chance to once again practice their legendary CS. If the bean counters have ruined that like they have other companies, I will have purchased my last RCBS tools.
Hey! I am 70 years old now and have everything I need to load for and shoot the guns I own, so stepping up to Redding for the few things I will need in the future will be a small pill to swallow.
 
I just had an excellent experience with RCBS Customer Sevice last week. I called them Thursday early afternoon and recieved my items in the mail Wednsday afternoon. No charge.

Every contact with lee customer service was totally worthless,

With RCBS 100% total satisfication every time.
And as recently as this week.
.
 
Tagging in to see what RCBS CS says.
I’d wonder if that die has been like that since day one. You’d have to be really hammering on that thing to move metal. Think Forged in Fire.
 
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