RCBS 9mm die set up question

**Brian19** · Jun 25, 2021

I purchased a 9mm RCBS die set. I had previously been using a Lee die set. The bullet seat and crimp die came with two bullet seaters. One labeled 9mm FP, the other labeled 38 RN. I am reloading X-treme, 115gr RN copper plated, so I used the 38 RN bullet seater.

I feel that I am only putting a light crimp, but even this is enough to deformed the nose of the bullet. Attached is a picture of a bullet that I crimped and later pulled vs. a virgin bullet. Based on the light indentation line caused by the crimp, I felt it was not excessive, but still the bullet nose gets deformed.

thank

you in advance for the advice.

gunzby · Jun 25, 2021

I'm just taking a guess, but I'd say that you are crimping before fully seating and the bullet is soft enough to compress instead of breaking the crimp and scraping down.

I use RCBS in 9mm, but I use the Lee FCD to crimp after seating.

Edit: if you are going to crimp separate put an unbelled case in the shell holder and screw the seat/crimp die down until the crimp ring contacts the case, lower the ram and unscrew the seat/crimp die one full turn and lock it down.

higgite · Jun 25, 2021

I’ve loaded a lot of X-treme plated bullets with a combo seating/crimp dies and it looks to me like you’re overcrimping. All you want to do is take the flare out of the case mouth, not really crimp into the bullet. You should see no more than a very light ring, if any, on pulled bullets. Extra seating pressure could be causing the nose of the bullet to be deformed by the seating stem. And/or the bullet profile doesn’t match the seating stem.

AJC1 · Jun 25, 2021

Honest moment, after getting every 9mm and 38 seating stem made by rcbs I now use bullets with a flat meplat. Mine never distorted to that level. You could 1. Have a custom seating stem made, 2. Modify the one you have with epoxy, or JB weld or 3. Use a different style of bullets. I have had to chamfer and debur rcbs seating stems for bullets coming from lead rcbs molds. Dispite not owning a single hornaday die I think there availability and pilethra of stems is a great.

FROGO207 · Jun 25, 2021

I agree with the second poster. You should be just removing the flare on a 9MM. That is the definition of a taper crimp. Any that I pulled have some scuff marks on the side where they rubbed against the brass but no visible ring where the mouth is. You are way overcrimping them. Try lightening up the crimp and check for plunk/turn and falling out of the chamber. Probably the only thing holding the brass in the chamber propperly is the extractor. No crimp should help with your accuracy as well. Flaring die and bullet size should hold your bullet in place.

Walkalong · Jun 25, 2021

Agreed, use just enough taper "crimp" to remove the bell. Neck tension does all the work.

**Brian19** · Jun 26, 2021

Thanks, all. I’ll lighten up the crimp. Like you said, all I was looking to do was remove the bell from the expander die.

Walkalong · Jun 26, 2021

It's extremely easy to adjust for too much crimp, it takes such a small amount.

lordpaxman · Jun 26, 2021

Congratulations! Looks like you just invented the “Method to create a Flat Point from a Round Point”!!! And to think I had to order flat points….
As others have pointed out, seating and crimping in the same operation is tricky, you may want to try to do that in two separate operations. If you want it in one, you might want to measure the case lengths, and set up the crimp on the longest case length you have. Otherwise you’ll be fighting the same problem, again. Good luck.

RCBS 9mm die set up question

Brian19

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gunzby

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higgite

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AJC1

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FROGO207

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Walkalong

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Brian19

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Walkalong

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lordpaxman

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