pegrannan@gmail.com
pegrannan@gmail.c...
12 posts
Joined July 2010

Buldged cases

I have a 550C/9mm(Dillon Dies)/Missouri Coated 124glrn bullets and not all rounds pass the case gauge.

So my last attempt I ran 100 + rounds through Resize and decapping only. I picked out 80 that all passed the 9mm case gauge test. After loading those 80 rounds I had 2 or 3 that did not pass the case gauge check as I was expecting them to. Is that normal? I've been playing with the case bell but maybe can't seem to get it just right? I guess I'm not sure how much bell is really needed. At one point it was removing some of the coating which I figured was not enough.

Does anyone have any suggestions or can recommend what is the best way to determine how much case bell is needed?

Resize looks to be about .375, bell is approximately .386.
dillon
Administrator
dillon
3,110 posts
Joined July 2007

RE: Buldged cases

This part of the forum is for Mr. Bulletfeeder Setup questions.
To answer your question, you probably need to crimp the case mouth a bit more. The taper crimp die is what removes the flare and squeezes the case mouth firmly against the side of the bullet. On a loaded 9mm cartridge, the diameter measured at the case mouth should be. .377-.379".
Another possibility is that a deformed case rim is preventing the cartridge from going completely into the gage. If the loaded cartridge enters the gage up to the rim, reverse the cartridge and see if the case rim enters the gage fully. If it does not, then a deformed case rim is preventing the cartridge from fully entering the gage.
pegrannan@gmail.com
pegrannan@gmail.c...
12 posts
Joined July 2010

RE: Buldged cases

Thanks and after the crimp it measures .375 and I did try to put the cardrige in the case guage rim first and the rim does go in.
dillon
Administrator
dillon
3,110 posts
Joined July 2007

RE: Buldged cases

Back up your crimp slightly. That is a bit too much, which can cause the case below the crimp to bulge out a bit.