SIGforum
Case shape

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April 02, 2019, 07:05 PM
Roadrunner2212
Case shape
Hi
I’ve been reloading for a couple of years now, primarily 9mm and .45 ACP. I,ve noticed on some cases after seating the bullet, the case has a coke bottle shape for lack of a better term. Not all of the case are like this. My flaring die is set so the bullet just starts but not able to enter pass the radius on the bottom of the bullet. Is this normal or do I need to adjust the sizing die or the flaring die a little. They are Lee carbide dies set per the manufactures instructions. Does this affect the case from sealing off inside the chamber or is it nothing to worry about.

Thanks.
April 03, 2019, 08:04 AM
Blue68f100
The bottle neck shape indicates you have good neck tension. Quite common with the 9mm tapered case. The 45acp can or not depending on the thickness and size of the sizer. I think your ok just as you are. The ones that do not show a bottle neck I would confirm you have sufficient neck tension.


David

P229R 9mm, Nitron, Beavertail Frame, Night Sights, DA/SA, SRT & Short Reach Trigger
April 03, 2019, 06:09 PM
Roadrunner2212
Thank you David
I do a light taper crimp on both and measure a before and after and getting around a .001 to .0015 crimp so I feel I should have decent tension

Thanks again
April 03, 2019, 08:47 PM
valleyforge.1777
crimping can loosen the neck tension.... be careful about that (and you don't even need to crimp other than to remove the belling)

The coke bottle appearance is normal and expected for reloaded 9 mm rounds. Unless you have the equipment used by the commercial loaders, if you're doing it right your reloads should have the coke bottle appearance. As mentioned, the 9 mm case is tapered, inside. Can't see that by just looking unless you cut through one of the cases lengthwise.