Rust on S&W Shield 9mm?

[12Pump]

I just recently bought a Smith and Wesson 9mm Shield subcompact and fired it all of 15 times. Then I cleaned and loaded it for a few weeks, and then unloaded the chambered round and discovered a ring of what appeared to be rust on the area around the firing pin. I put a drop of oil there and rubbed it and it came off.

I'm surprised to find rust on a brand new gun so quickly! But was it actually rust?

 

[Riomouse911]

Rust if the finish wore off and it’s humid-salty air where you live, or maybe brass residue from brass cased rounds (my guns get this a lot) or even polymer residue if they were steel cases.

Next time you shoot it, put a drop of oil on a clean white patch and rub the spot to see if it’s rust or firing residue from the cases. If nothing else the very light oil coating will help keep slide/breech steel from oxidizing better than unprotected steel will.

Stay safe.

 

[BC17A]

Not uncommon. I make it a point to remove the striker/firing pin from every new gun I purchase and clean the channel with a bore brush and Q-Tips. I've seen rust residue on several.

 

[Spats McGee]

I'll need to take a closer look at mine, apparently.

 

[Outlaw75]

Rust if the finish wore off and it’s humid-salty air where you live, or maybe brass residue from brass cased rounds (my guns get this a lot) or even polymer residue if they were steel cases.

Gummed up lube from the factory, maybe? I bought a Shield a couple of months ago. I gave it a pre-first range trip cleaning and noticed that it seemed to be lubed with some type of thick lube. Thicker than most gun oils, anyway.

 

[rdnktrkr]

I have a couple of Shield 45s that I've had for years and have never noticed anything that looks like rust, I clean and wipe mine down with Eds red.

 

[Zaydok Allen]

Keep an eye on it. Try different ammo. Brass vs nickel cases. Watch humidity levels and see if there's a correlation. If oil was on the breach face when loaded, and it has been dry, some of them will gum up a bit. Hoppe's will do this, but typically it doesn't happen that fast. If it is oil, then I wouldn't trust that round.

 

[12Pump]

Rust if the finish wore off and it’s humid-salty air where you live, or maybe brass residue from brass cased rounds (my guns get this a lot) or even polymer residue if they were steel cases.

Next time you shoot it, put a drop of oil on a clean white patch and rub the spot to see if it’s rust or firing residue from the cases. If nothing else the very light oil coating will help keep slide/breech steel from oxidizing better than unprotected steel will.

Stay safe.

Well, the finish isn't worn off that spot at all. The gun is brand new. And there's no salty air where I live. It could be brass residue since I was using brass cased ammo. I'm surprised there would be any residue coming off a brass case though.

 

[Riomouse911]

You didn’t add a photo so we were left to guess about possibilities.

This is the breech face of my Glock 34. It has about 6,000 rounds through it now but it’s had this yellow circle on the breech face since the first time I shot it.


Brass is a lot softer than the breech steel, plus the cartridge case is being driven rearward under great pressure every time a cartridge is fired. That impact is bound to swipe molecules of brass off and deposit them on the breechface at every shot.

Stay safe.

 

[12Pump]

You didn’t add a photo so we were left to guess about possibilities.

This is the breech face of my Glock 34. It has about 6,000 rounds through it now but it’s had this yellow circle on the breech face since the first time I shot it.
View attachment 939639

Brass is a lot softer than the breech steel, plus the cartridge case is being driven rearward under great pressure every time a cartridge is fired. That impact is bound to swipe molecules of brass off and deposit them on the breechface at every shot.

Stay safe.

Yes, that's pretty much what mine looked like too! I think I got it all off when I wiped it with an oily patch though. Aren't you able to remove yours?

 

[Riomouse911]

No, it’s pretty much on there from now on. It’s just the way these things work; gun parts under pressure or friction will show some wear before the other parts that aren’t will.

This is like the black rings around revolver cylinders; you can clean it with flitz after every time you shoot...but it’ll just return on the very next pull of the trigger. Since this is inside the chamber and not visible like a revolver cylinder you will be the only one who would even know its there.

Stay safe.

 

[Reloadron]

A simple Google of "ring around the firing pin" will get you several dozen hits with a few dozen causes. The most common cause and one I have seen frequently including on several of my own guns is:

You didn’t add a photo so we were left to guess about possibilities.

This is the breech face of my Glock 34. It has about 6,000 rounds through it now but it’s had this yellow circle on the breech face since the first time I shot it.
View attachment 939639

Brass is a lot softer than the breech steel, plus the cartridge case is being driven rearward under great pressure every time a cartridge is fired. That impact is bound to swipe molecules of brass off and deposit them on the breechface at every shot.

Stay safe.

Normally the brass leaves a yellowish brass colored ring but I would guess it could be mistaken for very light rust. You have problems when primers leak and actually begin etching away or eroding away your breach face and I doubt that is your problem. I believe what yopu are seeing is just some soft brass residue.

Ron