I looked at  my 40S&W today and was shocked to find RUST !!! I take good care of my guns and have owned, fired,and cleaned  this gun for about 7 years.It is an  E.A.A. Witness with a stainless upper half and a powder coated frame. This is how I cleaned it last time . With the gun disassembled first I sprayed all parts with an action cleaner called Rusty Duck(smells like stater fluid or break cleaner eaithier I think) then I scrubbed the bore with Birchwoods bore 2 in 1 bore scrubber then after all powder resadew was removed I used MillTec1 oil on all moving parts and Tetra gun grease on all parts that get friction . The rust looks to be located mainly on the slide catch pin  and the bottom of the bolt which is odd because it is stainless.I have put about 200rds through this gun over a seven year peroid cleanning after every shoot and never seen rust before today .Please Help me find out which product is causing the rust so I can get rid of it!

I should also mention the parts that rusted where still coatsed in oil so much so I could wipe the rusty oil off with my finger .

miltec. sucks at rust prevent, its not one, no matter what miltec says. as an EP lube it is great, mixed riight. tetra is a great grease i use it my self. only had a  verry small rust problem from it.  there are beter out there for rust prevent and lube.

for lube and rust prevent and a cleaner (CLP) try either Break Free  CLP, FP-10 from MPC, G-96,  there about the easiest to use, i only caution to watch the g-96 around some plastics. i had g-96 destroy those plastic covers on the all weather master locks. While all 3 will clean something on the lines of hopes works better for cleaning.

watch those gun scrubbers in a can, they suck out all the oil out of the meteal along with the carbon.  Miss a spot re oilijng you will get rust.

2-gun,

From the sounds of it I'd say 2 things are possible.

Chemical reaction from the lubes and cleaner or between the lubes,
Or flatly, plain old failure of the Lubes to preserve.

Have run some short term tests on a weather plate and have found plain old Valvoline 10-30 is better as a preservative than Militec, as is Hoppe's gun oil, and I'm suspecting Crisco might be better as well.

Seriously, the Militec might be a lube(Pressure ratings I have seen have shown the stuff to be slick but not so good on hig pressure points) but it is NOT a preservative in any manner.

Tetra is solid stuff as a lube preservative, it ain't the best, but is a darn sight better than about 80% of the stuff on the market.

This leads me to thinking that possibly the chem reaction between two or three of the cleaners/lubes used might be at hand.

Get the rust outta there, and try it again with nothing but the Tetra after you neutralize any cleaning residue with the Rusty duck or Isopropyl alcohol.

I hate rust!!!!
And you ain't alone in noticing Stainless steel will in fact rust.
The Neighbor dog decided to "Mark" my new All stainless BBQ grill the other day and it's rusting where the Cur Peed on it.

There's a load of rubber buckshot in the backdoor gun with the Mutt's name on it!!!

Also have had a stainless colt rust a bit on the MIM parts after a day or two camping/Backpacking without cleaning while using Breakfree as a CLP.

Best lube preservative I have found is TW25B from Mil-Comm.
It was made for the Navy originally, for use on Deck guns and has a 500 hour continious salt water spray rating.

Whatever ya use, look into the incompatibility issue you may have found.

Best of luck!
S-28

Here's my plan based on yall's advice .

1.  Clean everything exept the bore with Rusty Duck and drimmel the rust stains with a felt pad  a drimmel tool and some mothers wheel polish. I found out the trick with the drimmel and mothers wheel polish when I bought a stainless steel mini-14 that had light rust and heavy carbon stains.

2. Clean the bore with Hopes #9 bore scrube

3.oil everything down with only Brake free .I bought some last week for my Ar-15 .

I will throw out the Miltec 1 and put the Tetra grease on hold. I'll stop useing the Berchwoods 2 in 1 bore scrube.

Sounds better.
Like S-28,I think the TW-25B is a much better lube/protectant than the Tetra.Heads and tails above the militec.I like the TW-25B and the MC-2500 oil alot.Thats all I use on my pistols these days.TW-25B inside and out and the MC-2500 oil goes in the pins,sear etc.Anywhere I cant get the TW-25B in I put a few drops of the MC-2500 oil.
Follow this for application on the pistols:
www.mil-comm.com/pdf/AI-M9-pistol.pdf
Get a sample of the Firepower FP-10 clp and try it too.FP-10
Raymond