[Doug S]

I tend to obsess when it comes to rust on a firearm. Today while cleaning my Sub 2000 I noticed a strange rust color on the metal surrounding the barrel/feedramp area. This is the round section of metal that appears to surround the actual barrel/feedramp (the barrel feedramp portion appears as a smaller insert inside of the larger circle of metal which is inset into the polymer). The feedramp portion of the metal is totally silver, but the outer circle of metal is a brown rust color when held under a flashlight. Without the flashlight it just appears to be dark in comparison to the silver barrel area. This section can is easily viewed when the gun is folded. Have any other Sub 2000 owners noticed this? Could it be just the color of the metal, or does it sound like rust? The gun has been thoroughly cleaned and oiled after every range session. On a positive note, I put another 50 rounds of Silvertip hp through the Sub 2000 without a hitch. Total is now 300. Thanks for any help.

[Third_Rail]

I've not used a Sub2000 before, but could it be brass/copper fouling of some sort?

[Doug S]

That's what I am hoping. Thanks for the response.

[Third_Rail]

My advice re: "is this rust?", is that if it's rust it's usually more than noticable - never really a question about it that I've seen. Try some copper cleaning/bore cleaning solution on a patch, rub the area. If it turns blue/green, it's copper fouling.