pre-27 front sight ramp pitting

Sleeping in the safe , my pre-27 3,5" has a strange pitting , rusty, along the welding between the ramp and the front sight.
I gently brushed and removed the brownish spots, but of course the blueing has gone, and the surface is rough where the corrosion occurred. First question: is it enough to keep it oiled and in a dry environment to preserve it from the progression? second qustion: is it normal oxydation or, as I think, some sort of reaction between the carbon steel and the welding material?

pre-27 front sight pits

Sleeping in the safe , my pre-27 3,5" has a strange pitting , rusty, along the welding between the ramp and the front sight.
I gently brushed and removed the brownish spots, but of course the blueing has gone, and the surface is rough where the corrosion occurred. First question: is it enough to keep it oiled and in a dry environment to preserve it from the progression? second qustion: is it normal oxydation or, as I think, some sort of reaction between the carbon steel and the welding material?

sorry, I forgot the attachment....

There is no weld there. Actually the ramp has a piece on the bottom of it that fits in a slot in the barrels rib. There is a cross pin that is polished flat and almost invincible. I think what you have going on is some kind of substance has seeped between ramp and rib and is causing the corrosion. Possibly blue salts that never got neutralized. Remove grips soak it in Kroil or a mixture of kerosene and automatic transmission fluid. for a day or so and let it soak into the seam

Makes me wonder if the OP owns a 4" revolver cut back to 3.5" for one reason or another.

I have a pre 27 6 inch that had that issue. I soaked it in Kroil and then wiped the exterior off, hoping there was some penetration to stop it. I better check it as I don't shoot this one. Probably the best solution is to remove the sight and clean all affected surfaces and oil before reattaching front sight. However, that will require a round headed pin to reattach the front sight, which I do not have, and is way too much trouble at this point.

This is not an uncommon occurrence in pre 27 guns of the mid 50s. I have read of other occurrences here on the forum.

MichiganScott said:

Makes me wonder if the OP owns a 4" revolver cut back to 3.5" for one reason or another.

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I would imagine that it is the original length. This was a common issue in this era of guns. Steelslaver is correct, the bluing salts got under the ramp and were not neutralized when the finish process was completed. The ramp is indeed pinned on and the factory guys did a wonderful job blending the heads of the pins with the raised rib.

I have a 38/44 Outdoorsman dating to 1955 with the same characteristic pitting on the ramp. The gun is otherwise immaculate and I am not touching it.

Soak the affected area in CLP until softened then use a pure copper tool to scrape the corrosion off. Then keep coated with CLP to prevent further appearance.

Once it forms bumps and rust spots, it needs to be removed, and usually a solid copper tool is best.

It's always been a hot bluing salts problem as far as I was concerned.
The salts get under the two pieces, rib and sight ramp, and don't get flushed out afterwards. The salts are hydroscopic (sp?),,they attract moisture from the air afterthey dry and as such start to rust the metal in there and it shows along the seem betw them.
Oil won't flush out the salts or kill the chemical reaction problem.
Simple boiling water will flush them out, but the problem is that the tight fit won't generally allow a good clean job of it and some remains in there to rust.
Disassembly, clean-up and reassembly is the general cure.
Rounded end pins for reassembly usually. Sometimes extra polishing is needed to get rid of pitting done by the rust sitting there for long term. Then a reblue with the parts separated so the salts don't collect and cause the problem again.

...A question I have always had regarding this and the bluing processes at S&W,,,
this problem shows up on pre-27, and Mod 27's and some other models of S&W from the same era. I've seen it on early 29, pre 29, ect.
I've seen it said over and over that during this time frame that Carbonia Blue was still in use at the factory,,IIRC right up into the early 70's.

Carbonia Blue is a dry process and will not cause this damage to happen.
There are no 'salts',,no water soln bath at 300F that the parts are soaking in. Nothing to seep into the seem and get locked in there unable to get flushed out. No boiling water bath cleaning of the parts is done after Carbonia Blue in fact. They are dry.

I had always figured from the look of the blue and working with the guns and on them that the bluing was nothing more than hot salt blue used Post WW2.
The problem seen with these front sight ramps rusting is a good indication of it and a problem seen other places too from incompletee rinsing after the process.

So what's the real answer,, were they using hot salt blue in the pre-model era ,,and that causing the rust as it is immedietly suspected when one of these ramps/rib rust problems is seen.
Or were they using the Carbonia Blue well into the late 60's or early 70's as often said.
Or perhaps a mix of the two processes?

I have a pre-model 28 with the same issue. It bugs me because the rest of the gun is really nice but not enough to have the whole thing refinished.

I have two mighty fine nickel plated 5" N frames as a result of bluing salts leaching out from under the front sights of 6 1/2" barrels.

Any mid 1950's model is subject to this problem. Many barrels were replaced by Smith due to customer complaints. Problems on many in drier climates didn't show up until years later.

Once the damage is done, cleanup, spot polish, and blue touch up is the only practical solution. However it will happen again unless the salts are neutralized.

My solution after doing the blue touch up is to hang the revolver muzzle down with the entire front sight base immersed in a solution of water and baking soda for 24 hours. Rinse, get hot, and completely dry with a hair dryer. Oil well.

Browning had a similar problem years ago and the shotguns affected were known as "salt guns".

So, if I have one of these nickel pre-27s with a pinned blue front sight and this problem hasn't emerged at this point in the gun's 63 or 64 year-old life, am I safe? Is there any preventive action that should be taken, or, should I take a chill pill and stop worrying about it?

BlueRidgeBoy said:

So, if I have one of these nickel pre-27s with a pinned blue front sight and this problem hasn't emerged at this point in the gun's 63 or 64 year-old life, am I safe? Is there any preventive action that should be taken, or, should I take a chill pill and stop worrying about it?

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1. Likely safe.

2. See post #12 above.

Browning had a similar problem years ago and the shotguns affected were known as "salt guns".

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In the case of the Brownings, the issue wasn't that hot salts bath bluing but rather the method used to season the wood used for stocks. There was some type of salt used in an attempt to hastening the seasoning/drying of the stock blanks before machining and this caused rust to form where the wood touched the blued steel.

At the time the Smith & Wesson guns with the sight base and blade were pinned to the barrel rib, the company was using the Carbonia Bluing method which is done in an oven and was a dry process. Smith & Wesson discontinued the Carbonia Bluing around 1977-1978. Having rust grow out from that seam suggests to me a hot salts bath refinish which wasn't neutralized correctly but I could be wrong. I have been before and will be again. At any rate, I think comment #9 is headed in the right direction.

I suppose that the sight base could have been hot salts blued with the rest of the gun being done by the Carbonia method but I don't know that for sure.

Bruce

Yeah, something doesn't jive. Roy himself said: "....the factory changed from carbona bluing in the late 1970s to the penetrate bluing process."
Roy Jinks

I'm wondering if it was an acid wash used in the 1950's to clean the metal before bluing

The FN 'salt cured wood' was done with plain old rock salt.
It was not a new approach to curing wood in a hurry,,it had been done before but never by a large firm like FN.

I had some pictures at one time of the blanks and they being covered with shovel fulls of salt by workers as they were stacked for the drying process.
Water literally running freely from the pile of wood later on in the process.

Ruger is suspected of using some salt cured wood for their No1 rifles at one point in production.
The damage the salt cured wood causes to the steel frames and fittings is unmistakeable.
Dozens and dozens of fixes abound for stopping the usually high grade wood that went through the process from re-rusting the metal after one of the guns has been all fixed up.
But they fail sooner or later and though the gun can look pristine on the outside, they can be severely eaten away inside from salt corrosion.
Browning used to replace the 'salt wood' on warrenty,,but not anymore as I understand.
Ruger replaced a fair number of stocks & forends but never really admitted to knowingly using any salt cured wood ,,that's the way I understand it anyway.

I have a 38/44 Outdoorsman suffering the same problem to a lesser degree. Since it is a known "factory" problem, and it has been stopped, I have elected to do nothing more at this point. The gun has been shot and is a solid 96 - 97%, so I'm not going to reduce it's value further.

I think S&W and most (or perhaps all) other major manufacturers in the world were using hot salt bluing before WWII began.

Salt can be washed away. It cannot be not "neutralized", as is so often incorrectly asserted. For more info, or if you are having trouble falling asleep, read here...

What chemical neutralizes salt? | Reference.com

I think S&W and most (or perhaps all) other major manufacturers in the world were using hot salt bluing before WWII began.

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Ah....No. Not in the case of Smith & Wesson. Now, if you want to speak to Colt.

With regard to the terminology "neutralizing the salt", it is technically incorrect I suppose but most folks got the point of the statement I believe. For those who did not, I apologize for misleading you.

Bruce