question about 9mm sizing die marking the case

[greyling22]

so I've loaded a jillion 9's over the years with my lee carbide dies, and they have all left these blackish markings on the cases that go away if I use lube when I size. My straight wall cases do not do this. I have tried taking the die apart to clean it and see if that did anything, but it did the same thing after cleaning. And it takes a lot of effort to size. I had some time on my hands this evening, so I thought I would ask: Is it just something to deal with and I just use lube, or do I need to clean my die better, or change my case prep, or something? I don't want to get caught in a pattern of just doing something over and over just because I always have if I can help it.


The 2 empty cases on the left are my tumbled brass. The left 2 loaded cases are what it looks like if I don't use lube. The case on the right is a loaded round with lube.

(my mold is often not quite hot enough when I start casting, and I don't cull aggressively, so I have some wrinkly bullets. don't judge me )

 

[gamestalker]

I guess you don't tumble your brass?

Those marking appear to be carbon that's getting smeared down the case when you resize, IMO.

Though some folks do lube with carbide dies, it isn't necessary, I don't lube.

Those cases look way over crimped IMO. 9mm only needs enough crimp to remove any belling used during seating, it shouldn't be a visible crimp.

GS

 

[Urban_Redneck]

You can wear out a carbide sizing die.

I lube pistol brass with Hornady One Shot, a 3 second blast into a gallon ziplock bag, add 200-300 (9mm) cases, roll them around, and dump into a bin to "dry" for 5 minutes. Press runs smoother, no sticky lube to clean off

YMMV

 

[FROGO207]

My carbide dies do the same thing on 9MM if I polish before depriming. So I deprime/size THEN run them through the SS pins I presently use. No more problems. You do have to inspect the primer holes for stuck media and remove but I do that when I final check the brass after belling the necks. Then just prime and load em when ready.

 

[chris in va]

Probably need to clean out the die. You'd be surprized what junk builds up in there.

 

[snakeye]

Looks like the die was machined a tad too small and causing it and carbide will really not wear much over time and you said it had been happening for years.... I would call Lee and ask them what is could be.

 

[cfullgraf]

I( agree with gamestalker, you might have something built up inside the die.

Try polishing out the insides of the die with some 600 grit or so emory cloth or wet/dry sanding paper.

I do not normally use any lubricant with my carbide dies except I have started spritzing a little lubricant on large diameter cases such as 44 Magnum or 45 Colt. It makes sizing a bit easier on the big boys.

 

[greyling22]

I do tumble, though I admit that I let my media get rather dirty. I tried cleaning the die with powder solvent and a q-tip, but I could get more aggressive I suppose.

But yeah, redneck, that is what I have taken to doing. and it works, but if I didn't have to because of reasons that's good too.

 

[Jesse Heywood]

Start your cleaning with a bore brush and solvent.

 

[cheep]

Do you get that when you size or seat/crimp? Which die leaves the marks???

 

[243winxb]

my media get rather dirty

Time for new media.

 

[Shimitup]

Wouldn't hurt to get a drill and an old .44 cal bore brush you don't mind ruining and get after it with some carb cleaner to really clean it up. Compressed air after all of that if you have that option. At least that will rule out dirty dies if you still have the problem.

 

[moxie]

Looks like excess bullet lube being dragged down the cases during the seating/crimping step, NOT sizing. Have you got a pic of a sized case?

And yes, those are way overcrimped. Only need just enough to remove the flare.

Or, OH NO, you might be post-sizing with a Lee Factory Crimp Die, dragging lube and lead onto the case.

 

[Potatohead]

Time for new media.

Or you can join the strange ranks of the media washers. (Or winnowers in Rule3's case)

 

[greyling22]

marks appear on the sizing stage. I'm not using the FCD. And the pictures may be misleading, there is not much crimp there.

When I change out to new media I still get the marks. They do go away when I use case lube. I have not had a chance to hit it with a bore brush yet. I've been doing a bathroom remodel at home in my down time.