SIGforum
Can a .380 round damage a P365?

This topic can be found at:
https://sigforum.com/eve/forums/a/tpc/f/430601935/m/4050018854

July 11, 2019, 11:19 AM
opticsguy
Can a .380 round damage a P365?
It looks like some got mixed in a box I had in the bottom of my safe. It stovepiped but ran 9mm fine after that.

I was testing out a new grip and flat trigger and it wouldn't hit the side of a barn after the .380 round went through. Wondering if a new barrel is in order.
July 11, 2019, 11:37 AM
MNSIG
I'd say it's unlikely unless the bullet got stuck and you fired another one behind it.
July 11, 2019, 11:38 AM
Chowser
You’ll be fine.



Not minority enough!
July 11, 2019, 11:44 AM
hjs157
I too would be surprised if a single 9mm Kurz fired in a 9x19mm chamber would cause permanent damage. Scrub the bore and visually inspect for any bulging or other abnormalities. I somehow wonder if the new grip and trigger are detrimental to your accuracy.
July 11, 2019, 11:55 AM
CAPT29
It is far most likely that the installation of the new grip and trigger has affected accuracy than firing of a .380 round.
The .380 probably only fired because it was held in place by the extractor because if it chambered like it should in a 9mm chamber it would have been too far forward in the chamber for the firing pin to reach it-unless you have a super long firing pin, which would then pierce primers on 9mms.


The Islamic terrorist express: Go directly to Allah, do not pass hell.
July 11, 2019, 11:55 AM
Anubismp
Should be fine in theory. I'd pop the barrel and look for a bulge with the following.

1. Look down the barrel at a light so you can see the rifling. If you see a dark ring then that's possibly a bulge.
2. Slide the barrel into the slide from the front like youre pointing at the firing pin, and see if it catches on the barrel before stopping on the chamber/recoil lug area.

If neither of the above is a thing I'd not think too hard about it. I ran a round of 40 through a 45 1911 and besides not cycling the slide it was fine.
July 11, 2019, 11:56 AM
cslinger
If several .40 rounds won’t damage a .45 1911 I think you will be fine.
Uhhhh, uuuhh friend mixed up some ammo many years ago. Wink Frown

I just about turned white when I realized what I had done and why I was having so many malfunctions. I was THRILLED to have all my fin......errrr my friend was thrilled to have all his fingers. Smile


Take Care, Shoot Safe,
Chris
July 11, 2019, 12:18 PM
ensigmatic
quote:
Originally posted by opticsguy:
I was testing out a new grip and flat trigger and it wouldn't hit the side of a barn after the .380 round went through.

I think it's more likely you than the gun.



"America is at that awkward stage. It's too late to work within the system,,,, but too early to shoot the bastards." -- Claire Wolfe
"If we let things terrify us, life will not be worth living." -- Seneca the Younger, Roman Stoic philosopher
July 11, 2019, 03:37 PM
sigfreund
Many 40 S&W rounds have been fired in 45 ACP chambers, many 9mm cartridges have been fired in 40 S&W chambers, and even a few 357 SIG rounds fired in 40 S&W chambers, all without causing any damage except to egos. The 380 Auto cartridge uses the same size bullet as 9mm, so I cannot imagine it would have any adverse effect.




6.0/94.0

To operate serious weapons in a serious manner.
July 11, 2019, 05:28 PM
opticsguy
I looked at the barrel when cleaning. A lot if chunks of stuff, but it cleaned up nicely. I would think lead and copper couldn't damage a steel barrel, but you never know.
July 11, 2019, 05:34 PM
DaBigBR
No problem.

If you haven't shot a 9mm through a .40 or a .40 through a .45, you know somebody who has. Case usually bulges a little and the gun often won't cycle, but otherwise not a problem.
July 11, 2019, 07:23 PM
FN in MT
I watched a guy with a Smith 25-7 a .45 Colt revolver ,spraying bullets at the 50 yd steel plate.

But the report was odd, so I walked over. He was shooting full boat .44 mags out of that poor Smith!

The rest is a long story but that revolver survived.
July 11, 2019, 08:51 PM
RAMIUS
I’ve done that a bunch of times, not a big deal.
July 12, 2019, 06:49 PM
dickwholliday
I noticed some rounds in an ammo can that appeared to be too long..... turns out my dillon 650 will sometimes load a 380 just like it was a 9 mm..... they functioned just fine.... d I c k


"Take a kid shooting"
July 13, 2019, 04:47 AM
egregore
The .380 is smaller (at the base) than 9mm Luger. I would expect the case to bulge severely at this point. Unless the case blows out I don't see how it could damage the gun. The bullet is the same diameter and there is enough power to push it out of the barrel, so no worries about getting a bullet stuck.
quote:
Originally posted by RAMIUS:
I’ve done that a bunch of times, not a big deal.

Is this hyperbole? A bunch of times? Anybody can make a mistake, but the same one multiple times says you need to review safety procedures, like only putting out one gun and its ammunition at a time.
July 13, 2019, 12:13 PM
RAMIUS
quote:
Originally posted by egregore:
The .380 is smaller (at the base) than 9mm Luger. I would expect the case to bulge severely at this point. Unless the case blows out I don't see how it could damage the gun. The bullet is the same diameter and there is enough power to push it out of the barrel, so no worries about getting a bullet stuck.
quote:
Originally posted by RAMIUS:
I’ve done that a bunch of times, not a big deal.

Is this hyperbole? A bunch of times? Anybody can make a mistake, but the same one multiple times says you need to review safety procedures, like only putting out one gun and its ammunition at a time.


I did it twice by accident at the range. Then I got curious and tried it a few more times just to make sure Big Grin


July 13, 2019, 05:30 PM
opticsguy
quote:
The .380 is smaller (at the base) than 9mm Luger. I would expect the case to bulge severely at this point. Unless the case blows out I don't see how it could damage the gun. The bullet is the same diameter and there is enough power to push it out of the barrel, so no worries about getting a bullet stuck.


Here's a pic of one of the casings I found

July 13, 2019, 05:45 PM
Jim Watson
There was one PD that would practice malfunctions by putting a random .380 in a 9mm Beretta magazine. The Beretta would feed and fire the .380, but not cycle; jam!
July 13, 2019, 05:46 PM
odin
I think that's called "fire formed"!! Big Grin Big Grin
July 14, 2019, 05:47 AM
sigfreund
quote:
Originally posted by Jim Watson:
There was one PD that would practice malfunctions by putting a random .380 in a 9mm Beretta magazine.


Ooh! Good idea.
Thanks for mentioning that.




6.0/94.0

To operate serious weapons in a serious manner.