Rusty Stainless Montana Rifle

[Jeff 907]

Hello, curious if anyone else experienced this? I bought a MRC V2 .458 Lott lefty (new) last year for the sole purpose of a Cape buffalo hunt that was supposed to be back in May. I did their recommended barrel break-in and was practicing regularly until March. Put the gun up after the trip was cancelled in April. Pulled it out this week to shoot and found the receiver rusted. Not even six months and it’s already started to pit. I have never had a firearm rust this fast or bad this quickly. I used some Flitz along with a 12g barrel swab and drill to get some cleaned off, but still needs work. Needless to say I’m pretty miffed about this.
Does anyone know of a gunsmith in the Anchorage/Mat-Su area that can help or any advice on rust removal? Thanks.

 

[bruce moulds]

maintainance has its own rewards.
bruce.

 

[leslie hetrick]

that realy sucks.

 

[1dirthawker]

Andy hawk is a great smith in anchorage

 

[1dirthawker]

907 562 0881

 

[sestoppelman]

Did you clean and oil it when you put it up? SS does rust, it just usually takes a little longer.

Get some WD40 and scrub it with steel wool pads, most of it will come off and what doesn't, oh well. Unless the bore is rusted too, then that's a whole other animal.

 

[Jeff 907]

Thanks for the replies. I’ll try calling Andy Hawk on Monday. It was cleaned prior to going in the safe using Bore Tech Eliminator followed by Lucas Extreme Gun Oil.

 

[sestoppelman]

Guess the oil didn't make it to the right places.

 

[Jeff 907]

Guess not. Perhaps Montana’s need to be dunked in an oil bath.

 

[Bullthrower338]

I’ve got the same rifle in 416 RM and live in the gulf coast, guns love to rust here, but not a problem. That is crazy, does the gun go from hot to cold and sweat a lot where it is stored? Looks like it will clean up though. Good luck

 

[Wyatt Smith]

Did you clean and oil it when you put it up? SS does rust, it just usually takes a little longer.

Get some WD40 and scrub it with steel wool pads, most of it will come off and what doesn't, oh well. Unless the bore is rusted too, then that's a whole other animal.

Good stainless won’t rust, I’ve seen stainless pipe fittings that move some really corrosive stuff (liquid calcium, anhydrous ammonia and the like) never rust. Rifles must be made of a different grade of stainless steel.

 

[sestoppelman]

I know that rifle SS is not the same as others, but I have seen good SS rust as well. Put something around salt water for a while and see what happens, even good SS will rust.

 

[sestoppelman]

Something for the OP

How To Remove Rust From Metal

If you have a set of stainless utensils or even some gardening tools that are rusty, don't toss them. You can salvage them with just a bit of elbow grease.

home.howstuffworks.com

 

[Hunter4752001]

Sometime back I cleaned a stainless Howa with one of the foaming bore cleaners. Must of got a few drops in the action which didn't get caught when I dry patched the barrel a followed by oiling. Long story short, next morning there were a few red spots (more red than normal rust). I can only put it down to a reaction between the particular type of stainless and the bore solvent used. Happened way faster than actual rust would even in a standard steel barrel.

 

[IdaRam]

Generally speaking, the type of stainless steel used in rifle barrels and receivers is 416. In some instances 17-4 is used for receivers. 416 (which can be 410 or 421) is used because it is heat-treatable and easily machined. In order to be heat-treatable it must contain carbon, meaning it is a ferrous metal and it will rust.
There really is no “good grade” of stainless, there are just different types with properties that are suitable to the application. Some of the most rust or corrosion resistant types, such as 316, are not suitable choices for parts such as barrels and receivers because they are not heat-treatable and difficult to machine, and would be very poor choices for the application.
The stainless used in the receiver and barrel of your MRC are almost certainly the exact same as you will find in virtually any other stainless rifle.
It does appear that there may have been some type of reaction between the cleaning fluid used and the metal. Clean it up good and oil it up and keep an eye on it. About all you can do. If there is corrosion in the bore, well... bummer. But really not any fault of the stainless steel used in the rifle.
Sorry to see this happen though

 

[Shootist43]

Gentlemen, a little known fact is that under certain conditions Stainless Steel will rust faster than Carbon Steels. That is why stainless is not used as a through hull fitting on any boat or ship. Stainless steel isn't impervious to water and subsequent rusting.

 

[Hogpatrol]

May have happened but I've never seen 300 series stainless "rust". 400 series, free machining does rust. I would try some naval jelly on a q-tip on a small test spot. Keep it away from any blued surfaces. I use a silicon rag on all exposed surfaces and silicon spray where I can't get in with a rag.

Edit: I'd have it borescoped. Unless you had it oil coated, it too probably has rust.

 

[Ridgewalker]

Jeff 907, all of the above answers gave you good info. The 300 series are used in clean room conditions, but still need to be passivated (acid dipped) to get rid of the “free irons” on the surface. The 400 series, which can be heat treated for strength, are usually vibratory milled in a ceramic media, or highly abraded to remove the “free irons”. You cannot safely passivate heat treated steels without risking weakening their structure. JME, but times may have changed since I was active in materials.
Just my thoughts, but abrading the surfaces should bring you back to normal. Alaska coasts are brutal on steels!
Best of luck!

 

[curtism1234]

Oil and VERY fine steel wool should take almost all of that off. It looks surface rust. I'd re-assess any permanent issues after; when pitting occurs it normally reappears a lot quicker. If there any rust inside the chamber, I'd pass this rifle offer to someone else. You don't want a cartridge sticking

 

[mdwest]

Good stainless won’t rust

Not true..

Even the best quality stainless will rust.. (best quality can mean a lot of things.. but whether we are talking about stainless that holds the best edge for a knife... or stainless that is most corrosion resistant against moisture.. or stainless that is most rigid and appropriate for barrel harmonics... it all rusts..)

Its possible to treat stainless with certain products and processes like melonite or tenifer that will make it incredibly corrosion resistant.

but that adds cost and time.. and more importantly, a lot of those processes cannot be conducted in the US.. (for example applying a tenifer finish involves acids and asbestos...)