Bronze rifle barrel or components?

[bearincamo]

Hello everyone, this is my first thread here and I have an interesting question.

The questions:

1: Could high strength bronze such as Manganese Bronze, Silicon Bronze, Nickel Aluminum bronze or Cupronickel Bronze be used for the barrel or other components of a gun?

2: What would be the pros or cons of using bronze for barrel, bolt, trigger, etc.


...
The discussion:

I am aware that during WW2, Browning/Colt once tested a nearly all bronze 1911 pistol and it performed well but was never put into production because of the high demand for bronze during WW2.
The thought for me is that I like the look and properties of certain types of Bronze.
When compared to steel, most high strength Bronzes have:
*Better thermal dissipation.
*Approximately equal or greater in tensile, hardness and fatigue strength to most common firearms steels.
*Low friction.
*Very low expansion or distortion from heat or cold.
*Doesn't change properties with minor or extreme temperature changes.

Knowing this, I wondered that maybe Bronze has a place in sport shooting. I understand that for military use it makes much more sense to use less expensive steel. But for sport shooters, Bronze could be a viable tool in getting the best performance while also having a beautiful look. I plan on making a Bronze barrel for my SMLE and re-chambering to 30-06 or .308. It will be a heavy 'bull' barrel about 7/8" thick.

What I want to discuss and hopefully learn is if bronze has been used by anyone else and what may be the good or bad of using it.
Also: will bullet casings stick in a bronze chamber? I don't see why it would. Bronze is used for bearings and other high friction'high pressure areas very frequently so I can't see why there would be any negative from using bronze.

The only negatives I can think of are that bronze is heavier and more expensive.

 

[bearincamo]

Nobody have any ideas?
I guess I will need to try it myself and let y'all know how it works out.

 

[Iron Worker]

Isn't Bronze softer then steel ? I've never heard of a Bronze file or drill bit ,bronze screws ,bronze nails ,bronze screw driver.

 

[Litehiker]

Bronze is a copper and zinc alloy. The first metal weapons (ending the stone age) were bronze. Later much tougher and cheaper iron weapons came along and were THE weapons to have. Greece use them as did Rome and all other nations through the Middle Ages. So, Stone Age, Bronze Age, Iron Age, and by the 1600s, Steel Age. (DISCLOSURE: I taught history for 35 years.)

So no, even the best bronze alloys would not be ideal barrel material. They would wear out faster and likely need to be heavier as bronze is not as strong as normal barrel steel.
Bronze cannons for black powder were made B/C they were lighter than iron cannon but black powder pressures were very low.

 

[bearincamo]

Actually copper-tin bronze is stronger than iron. The idea that bronze is weak is a misnomer spread by historians who didn't look into the facts of metallurgy.
Copper IS very weak and would NEVER be suitable for any weapon.

The switch from bronze to iron at the end of the bronze age was because tin was so rare something else was needed. It took nearly 500 years for steel to be manufactured to a quality higher than bronze. At the end of the bronze age, they were using blends of copper-tin-sulfur and getting a very high strength bronze. Some weapons have been found to have small amounts of lead which also makes bronze more slippery(I'm not sure what benefit this would have in a sword but in bearings it is irreplaceable.).
But throughout all of history bronze was always much more expensive. Making the more labor intensive iron based metals preferable. Iron is a much more abundant element. But even then bronze remained in favor for several hundred years after iron was worked into weapons. Until high carbon steel was available for low cost (due to iron mining in northern Europe and the eastern countries) bronze was preferred. The Arab nations were the first to take that iron and turn it to high quality steel. When tin became scarce people switched to iron based weapons. Once the switch was made, more people learned that art of iron working and iron became much cheaper. And iron based metals have been our choice ever since. But brass can be used for almost everything steel is used for.

It is interesting to consider that early iron swords can be broken by lade bronze swords. Bronze bends instead of breaking so if your sword was bent you could just hammer it straight again without losing significant strength. If your sword was destroyed you could just melt it down and re-forge it. So bronze had many advantages but cost was a big element and if theres no tin theres no weapons so you are forced to switch to a suitable material. That was iron. it was 'good enough' in the beginning but eventually became far superior.

Some bronzes from the bronze age were so well made that we cannot replicate the quality or purity today. (kinda awesome eh?)

Yes steel can be made stronger, harder, softer, more flexible, higher tensile or just about any other way. Bronze is made strong by its mix, the way it is forged and how it is hardened. Which cannot be done by heating and quenching but is done by compression. They hammer bronze to make it harder.

Now, modern bronzes are made in various blends to get different properties from the material. leaded-bronze is a very good non-lubricated bearing because of natural lubricity. Sulfur-bronze is strong and casts very well so is used for both drivetrain materials and statues. Phosphorous-bronze is very strong but the gasses given off while melted are poisonous. Manganese-bronze is extremely strong in relation to tensile strength, torsion strength and compressive strength. It is comparable to 1045 carbon steel on most respects
****(I will need to look that up again to get an exact comparison and I will post the data here.)****

It was my working with bronze materials and realizing that the numbers were high enough to compare with high strength steel that is normally used for swords and knives. that made me consider using it in a firearm.

The negatives are:
Cost (It is more expensive) and it isn't flexible like steel so it doesn't work well for swords.


Maybe Im still missing something but there is what I know from about two years of study.

 

[bearincamo]

In order to avoid any misconceptions or misinformation (especially from myself!)
I am going to look up hard data and from that either prove the validity of my thinking or prove myself completely wrong. LOL.

I really hope that this is possible.

I do know that there was at least 1 Colt 1911 built out of bronze during WW2.
Here's the link.

The Bronze 1911 pistol - The Firearm Blog

I will post my findings in the next post. It will be necessary for me to compile data from various charts and sources in order to find and assemble the information into a comparison chart. I will post that chart here as soon as i get it put together.

Thanks for bearing with my ramblings. I just hope to find weather or not Bronze has some desirable qualities and if it does, I want to find out what they are.

I have access to machine tools needed to manufacture any parts needed so maybe the best thing will be to find the information in detail and if the data looks good on paper then to make a simple single shot rifle with a steel barrel and a bronze barrel and test them to see if there is any value to the bronze over the steel.

Honestly this is exciting and fun and I hope that it turns out to further the general knowledge of firearms and shooting for everyone in the future.

 

[bearincamo]

Actually they make bronze bolts and nuts for military aircraft. Bronze is also used in landing gear and jet engine parts. It is also used for ships propellers, transmissions and drive shafts. Some engines use bronze valve guides. Some machine tools such as mill bits and chamfer bits are bronze. Metalworking hammers are sometimes made from bronze. Knives, pistons, air tools, cable, wire, hinges, pins, bearings, gears, chain, wrenches, screwdrivers etc. (Some drill bits are bronze coated to give better lubrication while dry cutting but have hardened steel cores for the cutting edge.) However, generally hardened steel is used to work softer steels which makes sense. It's WAY cheaper and works amazingly. Though it should be mentioned also that both bronze and steel are usually worked with tools that have Carbide working points. And carbide is much harder than almost any other metal.

 

[bearincamo]

@Litehiker:

Please don't take any of my comments to come across as correcting or disagreeing with your knowledge and experience in teaching history. I very strongly respect history teachers and I don't want to seem like some jerk who is discounting the work and effort and knowledge you have. I hope just to share what I have learned and what I know. And I am always willing to except when I am wrong and I am always ready to learn new things from those who are wiser than I am. I apologise that I replied without actually reading your comment fully and for that I am sorry. I was reading through the posts and realized I came off sounding like a big smart@$$ and I did not intend to!

 

[Canadian Bushman]

Bronze has no where near the hardness or tensile of steel.

Dont base your facts on iron because it is only one of many elements that make up the alloys of steel which are used for rifle barrels. Which are 416 ss and 4130 chromoly.

Not only is the hardness critical to prevent rapid wear, its tensile-yield relationship ( commonly referred to as toughness ) is critical to the way a barrel handles the stresses of the very high pressures of rifle chamberings. Steel also has a very good memory. It holds its shape when stresses become close to its yield. Most bronze alloys tend to deform quite easily and stay that way. If you ever see an old brass or bronze cannon they were quite thick. Thats because the not so thick ones exploded. How a materials properties hold up during excessive heat is another reason steel and especially stainless make good barrels. Most bronze alloys become soft and malleable at a much lower temperature than steel. Not a good property of a rifle barrel.

The stronger alloys of bronze that only approach the bottom end of the tensile of modern steels are very expensive to produce.

Where i work we commonly work with steels that run from tensile strengths from 130k-180k and some exceed 200k, with hardnesses ranging from 30Rc to 70Rc.

Steel is easy to work, affordable, holds its shape well, and also has an endless supply of heat treatments and surface treatments that make it a very viable and common option.

 

[Canadian Bushman]

When you look up these alloys which im sure you will.

Pay close attention to the elasticity, elongation, and deformation properties when comparing them to the most expensive alloys of bronze.

 

[bearincamo]

@Canadian Bushman
Thanks for the info I will be sure to include all those parameters in my comparison.
Your input is very valuable. The best hardness in bronze I have found so far is 110 ksi with a elongation rate of 8-11% and hardness of 52Rc. (I can't recall now what it was) Maybe that is enough for a firearm but the cost will probably be overwhelming.
I agree, steel is an amazing material and probably the most customizable metal known to man.
Thanks for the help! I will do my best to get a detailed list of materials of both steel and bronze for this comparison.


On an aside; what about using bronze for parts other than the barrel? Using a low friction material in areas of lower stress may be beneficial to reliability. Possibly reducing need for lubrication?

What are areas where a corrosive resistant, low friction material be useful on a firearm?

PS: Still working on my spreadsheet comparison.

 

[LeddSlinger]

Another thing to remember is that gunsmiths don't want to work with harder metals than 416 SS or 4130 CM. Those steels are the perfect balance of hardness and workability for long barrel life and ease of manufacturing. Anything much harder and tooling has to be replaced more often and tooling can be VERY expensive.

Lothar Walther employs T50 SS steel in their barrels which is much harder than 416 SS and does provide longer barrel life. However, due to the fact that T50 is very hard on tooling, many gunsmiths will not chamber a Lothar Walther barrel.

The same thing goes for wood stocks. Walnut is the most popular because it is the perfect balance of hardness and workability. There are much harder woods that resist weather better than walnut, but they can be extremely difficult to work with when shaping and inletting.

 

[Canadian Bushman]

Your input is very valuable. The best hardness in bronze I have found so far is 110 ksi with a elongation rate of 8-11% and hardness of 52Rc. (I can't recall now what it was) Maybe that is enough for a firearm but the cost will probably be overwhelming.

Exactly. Seeing how even cheap, low grades of carbon steel can be heat treated up to 110k - 150k very easily and still maintain their toughness makes them a better candidate for barrels.

Another thing to consider,
When most metals are taken to their max hardness and tensile, their yield will start getting closer to their tensile and elongation and elasticity will drop. This means they are becoming brittle. Not a bad trait for wear pads or something that will receive a slowly applied force but when over loaded or too quickly loaded, they will shatter like glass.

Bronze, aluminum bronze and beryllium copper are all excellent materials for dynamic functions. Threads, bushings, guide plates etc. They have good wear rates, just enough surface hardness, and low coefficient of friction that they can slid around on other metals all day with no lube and not gall up. These are the task i see those materials most commonly used for.

You will very often see bronze and alum bronze guide bushings and valve seats.

 

[bearincamo]

@DrillDog, @Canadian Bushman:
You guys are awesome. You have brought up thought points that make tons of sense.

@DrillDog: I agree that steel is so much easier and simpler to use. Plus far less expensive. Thanks for mentioning that though; my intent here is wondering if bronze type metals have properties that are desirable if cost were no concern. But both of you bring up the workability and function of the materials and those concerns play a huge part in the feasibility of using bronze for a gun barrel or even for other mechanisms within the firearm.
I am gathering that you could theoretically use bronze for all parts except the barrel without much consequence as long as the cost was not too deterrent. But to use bronze for the barrel would have to overcome some serious requirements. It may be workable in a small caliber rifle or handgun ammunition but even then it may be limited to lower pressure loads and/or require a thicker and thus heavier barrel. The last hurtle would be the rifling; yes smooth-bore would work fine because its smooth. But how well would the rifling hold up to the abuse. Would it require more smaller grooves or would it require less larger ones? Would a bronze barrel need a Ratchet or Wetford style rifling? I suppose one of the many styles would work. But then there is always the cost.

Thank you guys, I feel much more educated now.