Problem with rust on my FAL

[goon]

Well, after a bunch of tweaking, switching parts, and after drilling the gas port out a little, finally have my ORF Imbel working exactly like I want it to. I even have it zeroed almost perfectly. Despite my early misgivings, I am growing kind of fond of it. It is more controllable than my AK, even during rapid fire. It is also now just about equally reliable (no malfunctions in the last 500 rounds or so) and way more accurate.
The only problem I have left with it is that it is a magnet for rust. Every time I take it apart I find rust in the gas block and gas tube. I cleaned it yesterday and the entire gas system was crusted in fragile, speckled surface rust that was working at getting a foothold. The gas regulator was rusted fast eventhough I just moved it when I adjusted the gas to work with SA surplus last weekend.
It wasn't a big deal to clean and it didn't cause any damage, but still...
This seems to happen every time.
I have shot mostly Portugese and SA surplus, but also a little British and Austrailian stuff, as well as some handloads.
Should I just go ahead and assume that ALL foreign ammo is corrosive? Could that be my problem? This stuff doesn't look like the red wheatfield looking rust that I have seen result from corrosive ammo before, but I guess it could be.
The gun is parkerized. Is that kind of finish less resistant to rust?
Can anyone help me out with this?

 

[Bartholomew Roberts]

What type of encironment are you using/storing it in and what type of lube/protectant are you using on it?

 

[usp_fan]

Over on the FAL files, you will find this is common and not due to corrosive ammo. Most people say to clean and then run the gas system dry, however, if you don't want it to rust, you have to keep it well oiled. Since I started using (insert your favorite lube here) I've not had any rust show up in the gas system. FYI I've been using FP-10 and it does work and sticks around. Most of my gas fowling just wipes off.

The other option to oil is some sort of spray on bake on finish (paint).

Good luck,

--usp_fan

 

[goon]

Will having oil in the gas system present any dangers? If it is just a matter of foulig possibly sticking to stuff, I can live with that.
I generally just use a light household oil or Hoppes (the oil that comes in the orange squeeze bottle). I wiped the exterior down with 10/30 motor oil today because I am fed up with the rusting. I figure that if that won't stop it from rusting, I don't have anything else that will.
The environment is central PA. It gets anywhere from freeze your @$$ off cold to sweat your @$$ off hot. Today it is about about 90 and humid.

 

[Bartholomew Roberts]

Hoppes gun oil isn't the greatest protectant. I would give some form of CLP a try - Breakfree, FP10, Slip2000 Gun lubricant. Eezox also has a good reputation as a protectant.

 

[usp_fan]

Light oil in the gas system will not be a problem. Use a good quality oil made for weapon temps.

I'm in Ohio with the same humidity problems you've described. This seems to be the most reliable fix for FAL gas system rusting.

-usp_fan

 

[ny32182]

So you can see rust just by running a patch through the gas tube? And you can see surface rust on the gas regulator?

As far as I know, those parts are parkerized on my DSA, but I've never seen any rust on them? Maybe I'm not looking hard enough?

 

[MartinS]

I once mistook flakes of bullet to case sealant for rust in a SAR 1. I've kept a light film of oil in the gas system of this rifle, either Mobil 1 or Ed's Red and can get the parts as clean as I like.

 

[Matthew748]

Thanks for bringing this up. I just gave my DSA STG-58 a good once over and, sure enough, there was a very small amount of rust inside the gas tube. The regulator was fine though. Sucks to that “keep the gas system dry” nonsense, I am going to keep it lightly oiled from now on.

 

[boofus]

I went and cleaned and oiled the gas tube on my FNC after reading this thread. I figured you were supposed to keep the gas tube dry too, but to hell with that if it will rust.

I didn't find any rust inside it, but gobs and gobs of carbon and goo when I stuck a breakfree-soaked patch in there.

 

[ny32182]

I guess I'll check mine later on. Now you guys have me worried. How do I know for sure if it is rusting?

 

[Chuck R.]

How do I know for sure if it is rusting?

Just run a dry .45 brush into it, followed by a dry patch on a .45 jag. If it's rusting you'll see orange.

I keep my SA58 gas system lightly oiled. The manual that came with it contradicts itself a little. On page 36 it states to run a "lightly oiled patch" through the gas chamber, then on 37 it says to leave the piston and gas chamber dry.

I leave everything with a very light coat of CLP.

Chuck

 

[Cosmoline]

Sounds like you're using corrosive ammo. Just spray down the innards with M-pro cleaner or a homebrew to kill the salts.