Home Forums Hunting & Shooting Ask The Gunwriters Metallurgy of Older Firearms

If a firearm made in the 1800's can withstand a certain maximum pressure when it was new, can it withstand that same maximum pressure a hundred-plus years later, or is there a degradation of strength due to aging?

Does the metal become more brittle by just getting older?

I can't answer the question about degradation of strength, but if it is over a hundred years old, it more than likely was meant to be used with black powder.

Things to think about are hydrogen embrittlement, corrosion and mercury primers. These factors are inter-related. Both hydrogen and mercury alloy with other metals and make them brittle. Cracks can capture and hold moisture and drive crevice corrosion (top of crack with Fe+++ and tip of crack with Fe++, generating even more hydrogen as a byproduct of corrosion. Shooting blackpowder guarandamtees the presence of salts that attract moisture out of the air

Also, notch toughness in cold weather is a question. We did not have an understanding of cold weather notch toughness until after World War II, after so many Liberty ships sank.

Bottom line....baby that old relic. It MIGHT be able to take a goodly dose of pressure. Or it my plant a bolt or other gunpart in the center of your forehead.

The science teacher in me says that metal isn't going to alter it's structure without something acting on it. I just bought an "03" Springfield and there is a known problem with weak bolts in early serial number guns. Now was this a problem in say 1903 as well, or have these guns developed the problem. I think it was due to problems in manufacturing. I also bought an Enfield this Summer. I bought an Ishapore because it has been documented that they have better heat treating and stronger guns. I'm not hugely worried about an Enfield, but given the choice, why not the stronger one. I have an 1895 Mauser I shoot all the time. I think it's probably stronger than a new Rem 700. There's an issue of quality control. If the manufacture was in question, that's what would disqualify a gun to me. I bring every used gun I buy to my gunsmith before I shoot it. I know he can get X rays like you would X ray welds for deficiencies. There might be other tests as well, if you are really in doubt and want to shoot something.

Metal from that time period was mostly 100% iron. I don't know exactly when it was discovered that carbon could be added to make it into steel, for additional hardness and strength.

When using pure iron, the way to make a firearm stronger was to make the parts thicker. This was the idea behind the Colt Walker--to use heavier charges of black powder, make the barrel, frame and cylinder thicker and heavier.

Something else that I am not familiar with is the pressure difference between black powder. I have read that blackpowder operates at lower pressure than smokeless. Probably true, but can enough black powder be added to a charge to make the pressures high enough to burst the gun?

I believe shotgun barrels made in England are proof tested with black powder, so black powder might can be made to approach the yield point you would get with smokeless.

From reading about tests made from comparing smokeless powder loads to black powder loads in shotguns, the pressures are about the same for either loads in the 3 to 4 dram range.

That, in my opinion, would be reason enough not to fire older twist steel barreled shotguns with any type of powder. Many gun writers recommend only black powder for these shotguns, but if black powder can produce the same pressure as a 4 dram equiv. smokeless load, why would black powder be any safer?

As far as withstanding the same amount of stress a hundred years later, a gun in new condition probably would, but in 100 years, part of the barrel and breech could be rusted away, because of use and/or neglect, making it much weaker, if only because there is less iron then there was 100 years ago.

I realize this rambling did not answer your question, but it is about the best I can do.

Metal from "that time period"? Does that include the entire 1800's? Firearms metallurgy changed vastly from 1800-1899.

There's also a vast difference between "pure" iron, steel and cast iron. And no, the Brits do not proof-test with black powder these days--though yes, up to about 15,000 psi or so in pressure, black powder and the faster-burning smokeless powders typically used in shotguns loads aren't all that different.

Iron is not steel, nor is cast iron iron. Iron becomes steel when carbon, or other elements are added.

Iron is an element. Steel is an alloy. As I mentioned, I don't know when it was discovered that carbon could be added to iron to make steel.

Possibly, with the furnaces used during the past few hundred years, pure iron ore might have picked up carbon either from carbon monoxide from the fuel used to fire the furnace, or from other products of combustion.

I have a book written by Greener (sp?) In the book, there is a lot of information about proof testing barrel. There are even pictures. At the time, black powder was used to proof shotgun barrels. I don't know what that time period was, but I think it was after smokeless powder was invented.

Why they would prove with black powder when the gun was going to use smoke less has always been a mystery to me. Or, during this time period, the gun could have used both smokeless and black, but if so, I don't know why smokeless loads were not used.

I seems to me like they would use the type of powder that would exceed the pressure at which the gun was to be used on a daily basis.

I don't know all that much about the burning charastics of black powder. One thing I have never known is can you get enough black powder into a barrel to blow it up, or is there a limit on how much pressure black powder will generate.

Steel has been around for thousands of years, but not necesssarily of a type suitable for firearms.

Black powder is an explosive, if it is contained in a sturdy enough container and ignited it will produce a LOT of pressure. In my youth I worked at a couple of granite quarries, at one we regularly used black to break loose saw blocks from the mountain (seeing a 20 ton rock jump 3' into the air is rather amazing).

My black powder barrel proofing (modern barrels!) is double the maximum powder charge and seat two balls, the Dixie Gunworks recommendation IIRC. If you try it over snow or newspaper you should find unburned powder. While burn rate accelerates exponentially with pressure the exponent is much, much smaller for black powder. Supposedly the exponent for black powder substitutes is greater than that for black powder but I don't know that. So caution!

On re-reading I should have said proofing modern barrels just to be perfectly clear. I would hesitate(!) on period pieces, particularly shotguns, but for a regular shooter I would want it proofed for the most common mistakes, double charge or two balls. Pretty hard to make both mistakes at the same time but if you proof for that there's no doubt left.

Someplace I have heard that the Winchester 1873 was originally made with iron frames and changed to steel about 1880.

Handloading books list 30-40 Krag loads using modern powders that give the same velocities as the original rifles got in 1892.

1917 Enfield actions are sometimes used to build custom rifles in big-bore magnum calibers.

So...I suspect that the metallurgy was pretty good starting sometime about 1900 and I don't think it gets worse with age unless there's corrosion due to rust, black powder, ors something else. A worse problem is that some old actions, like the Krag, will not take modern pressures because the designs don't lock up as well.

Henry Bessemer was awarded a patent for the first method for mass producing steel of uniformly controlled quality in 1855. The science of chemistry already had grown sophisticated enough by then that they knew how to "measure" the ratios of the different components, and they had determined that the ideal amount of carbon was 1%, more or less, depending on the purpose of the steel. Bessemer's process was to pump oxygen into molten steel to drive off all the impurities, then add back the correct amount of carbon. There's still some dispute over just who did the inventing, but Bessemer gets the credit. The method is still pretty much the same today.

Before they began to understand the chemistry, steel making was equal parts art and voodoo and QC was very erratic.

The steel was also selected for machining qualities even
at the expense of strenght. They were good enough in there time.

can go atleast a lil older than tha the Swedish 1894 Mausers were made with outstanding steel for the time....the action is considered "weak" because its doesnt have all the features of a 98 but they have been rebarreled to a fair number of modern cartridges over the years and dont have any sort of a reputation for failing....couple of destruction tests ive read with them had them holding until well above modern pressures.....

I have read that one of the reasons the Swedish Mausers were so strong and durable was that Swedish iron ore was the most pure iron ore to be found anywhere.

That might be an explanation of the reputation that Swedish steel has in fire arms and cutlery and other applications where a steel with the least amount of impurities was needed.

I agree with hawkins that many times steel was selected for it's machining qualities instead of strength.

In the 1800s, there there were very few ways of machining iron or steel, or any metal for that matter. If it needed to be stronger, it was made heavier and of thicker steel, or iron, as the case may be.

I have read that one of the first uses for carbon steel was to be used as drill bits, taps and dies, lathe bits and milling cutters. There was very little, if anything that could be used to cut steel, even in it's soft state.

The strength of any given piece of steel depends on several things:

1. physical configuration of the part - it's size and configuration, including any design flaws or stress concentrations. For example - make a leaf spring with square sharp corners, it will tend to crack at the corners due to those stress concentrations.

2. Chemistry of the steel - what hardness & toughness can it actually obtain.

3. Heat treatment - two pieces of steel can have the same hardness, but markedly different properties, depending on the heat treatment. The notorious low-numbered 1903 Springfields are an example of good steel that was incorrectly heat treated, and proved brittle.

4. Cleanliness & metallurgical quality of the steel. Sulpher is good for ease of machining, but can make steel brittle - the notorious hull rivets on the Titanic were known to be made with very high sulpher content, which made them brittle. Any impurities can cause failure.

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Good designs can overcome metallurgy - for example the Winchester High Walls were famously strong, used for proof testing by Winchester well into the smokeless era. I think it was John Campbell who had analyzed some High Walls, and found them to be of relatively low carbon steel, but well made.

I have always been a little amazed by the low number of failures in older firearms if they are unaltered, in good shape, and used with loads for witch they were originally intended. I once saw an original matchlock fired with out incident, and when's the last time you heard of a M-91 Mosin Nagant blowing up even though many were made before 1900 and re-barreled many times. For many centuries, making good metal was akin to a "black art" and often methods and alloys were highly guarded secrets. The only way of testing a firearm was "proof" firing. While proofing establishes a basic level of safety, it is no indicator of long term safety. All of the much maligned "low number" M1903's survived proof firing and much use before any problems arose. What scares me more than than the metallurgy in old rifles is a receiver with internal stress fractures caused buy a slightly over sized barreled being installed. It can look like new on the outside and be a disaster waiting to happen.

kinda off subject but i watched a show last night on a specific type(brand would prolly be the more appropriate term actually) of Viking sword that was made out of superior steel....steel so well done that it impressed the hell out of a modern steel manufacturer...and this was made 1000 years ago....

through their trade routes some craftsmen for a period of about 150 years got ahold of some steel ingots they believe came out of Iran/Iraq area of today that were true high quality carbon steel with nearly no inclusions made via crucible method which was thought to have been developed only since the 1800's....

The early Egyptians were able to harden copper enough to use as razors, knives, swords, etc.

In the 1950's and 60's God only knows How many hunting rifles were built on surplus military actions. Some were reheat treated. Most probably were not. The possible problem is when somebody uses a surplus action for a magnum cartridge. Because magnums generate higher pressures than the cartridges than the military cartridges the actions were built for. You may have bolt set back.

Ludwig Olson, who wrote "the book" on Mauser, says a reheat treatment isn't needed. Various Gunsmiths will give you a different opinion on that.

I have two rifles with 1909 Argentine Mauser actions. I had both barreled for standard, not magnum, cartridges. If I got a "wild hair" and wanted to convert my 30/06 to 300 Winchester Magnum I would insist on having the action reheat treated first.