I just picked up a well used Sig P239 in 9mm; it's my first Sig.  It was a range rental so it has seen a lot of rounds and use but I got it at a good price.  I’ve noticed that cases shot from the P239 are bulged to the degree that the cases can’t be re-chambered.  I’ve never seen 9mm cases bulged that much.  Is this typical for this model?  See pics below.  Or is it possible that the chamber/barrel has been shot through enough that the chamber walls have eroded and are now out of spec?  Could it be a
timing issue with pistol?  Unlocking and extracting too soon?

http://home.attbi.com/~jbcanon/WebShots/sigp239.jpg

http://home.attbi.com/~jbcanon/WebShots/9mmcasebulge.jpg

The ammo is Remington Golden Saber 124 grain +P JHP.  No failures to feed, fire or extract in 300 rounds.  Shot some standard pressure 115 grain loads for comparison and they bulged too.

I don’t handload for 9mm so I’m not worried about recovering the brass but I was wondering if the bulging is normal.  Thanks for any tips.

J962
I have a 239 and I do relaod 9mm, there should be no bulging of the cases.  Do what you like, but I'd send it back to Sig for an overhaul were it mine.

Steve

I've never seen a chamber expand that much due except in some sort of failure. Are you sure it has a 9mm barrel in it?

Thanks for the feedback fellas.  It's a factory Sig barrel with "9mm Para" stamped on the chamber exterior.  None of my other nines have shown excessive bulging.

I have a feeling that this pistol has just seen a had a lot of rounds put through it and the barrel & chamber are shot out.  I'm planning to order a replacement from Sig and then seeing what's what.

Man, that empty shell casing has ".40" written all over it.  Even though it's marked 9mm, I wonder if you removed the barrel and dropped a .40S&W in it whether it would fit or not.  :)

It looked like a .40 to me too. Not to start an argument, but I've never seen a shot out chamber that was 'THAT' shot out. Usually it is the headspace that goes, not the diameter of the chamber.

I wonder if it has always been like that, and perhaps was actually a .40 but mis-marked as a 9mm.

I'd find a local gunsmith that has go/no-go gauges for 9mm and .40 and see what happens.

Does SIG chrome line their barrels? If they do, it could be a barrel that didn't get chrome lined.

Do you have a micrometer handy?  I'd be real curious to know the outside diameter at the base above the extrator groove and at the mouth of that case.  Also the inner measurement of the chamber.
BTW, the fired cases from my P239 9mm are not bugled like your example.

Cases should not be bulged. Get it checked out before shooting again.

Bulged Case:
OD base above extractor groove: 0.389"
OD case mouth: 0.385"
OD of case at widest part of bulge: 0.406"

ID of my Sig 239-9 chamber: 0.406"

For comparison, ID of my Glock 19 chamber: 0.390" (no bulged cases)

I'll send her to Sig and see what they can do.  Thanks to those with tips and verification.  BTW, a .40 S&W cartridge would not drop into the chamber.