9mm cast in Dillon rl1050

[DirtyDusty]

I started reloading 9mm cast on my older Dillon 1050. I am using Dillon does and they size the die down pretty tight. The powder funnel bells the mouth out slightly, but once you load the bullet in there the whole cartridge is hour glass shape. What’s the best way to fix this issue?

[sigep1764]

My Dillon dies do the same with my 9mm. Hasnt hurt a thing. I do use a powder thru expander that Lathesmith made for me because the standard Dillon one measured .353 at its widest point. It ended up seaging my boolits down. The Lathesmith expander goes deep enough for my 150 grain boolits and opens the case to an ID of .357.

[DirtyDusty]

Does he still sell them?

[Plate plinker]

The hour glass shape is not a issue. carry on!

[sigep1764]

Does he still sell them?

He makes them to order. Send him PM on here.

[jmorris]

9mm is tapered so if you are sizing it down so once loaded it looks like a snake ate a golf ball, back the die out a bit so it doesn't under size the case as much.

[cundiff5535]

I think the issue you are having stems from using Dillon Dies. The Dillon size die is an undersized die. It’s not as drastic as the Lee U die, but it is undersized. In addition I’ve read the crimp dies isn’t a true crimp.

I think changing your dies to Redding or even get an MA size will fix the prob and then crimp with a Redding taper.

As others mentioned though, the undersize case bottle shape will not hurt your bullet.

[dverna]

I have shot thousands of 9mm produced with Dillon dies on a 1050. There is a bulge, but it does not affect functionality in six different 9’s. I use the 122 gr TC Magma bullet.

[jmorris]

It’s pretty simple, what is the bullet diameter, what is a sized case diameter, at the mouth, before it is expanded and what is the wall thickness at the mouth?

[kevin c]

Despite all my years reloading 9mm, there's still a lot I don't know.

The 9x19 case is tapered; I've read that and seen the case's nominal dimensions on diagrams in many references. But just what does that mean for the case wall? Mic'd on the exterior, there is a taper going from above the extractor groove to the case mouth, but is there a taper internally so the space inside is a truncated cone, or does the thickening web compensate to make it cylindrical? I'm sort of leaning towards the last, otherwise I'd think there'd be a poor grip on the bullet just at the case mouth.

Even with .355" jacketed (and some commercial cast is sized the same) I could tell a 9mm round wasn't factory new from the cylindrical appearance of the sized case. Now I understand how a combination of fat .357's and the marked under sizing from the Dillon dies makes for the coke bottle effect. Still, all such rounds would pass a min spec case gauge.

I've run into another problem on occasion, an actual donut like circumferential bulge in the case that seems to come from a deep seated fat boolit hitting the web, or the same from the extra long custom expanding dies I was trying out. These definitely don't gauge. Avoiding this seems to need seating the bullet out more, using a bevel base design, reducing the bullet diameter, or not expanding so deeply into the case.

BTW, my factory Dillon 9mm expander ball mics out under .353", so it definitely puts the squeeze on cast boolits.