Metal Materials
260 Brass (C26000): A Complete Guide to Properties, Formability & Uses
If you are stamping electrical socket shells, deep-drawing ammunition casings, or crafting decorative jewelry, you need a metal that is both easy to shape and visually appealing. 260 brass—also known as cartridge brass, alloy C26000, or 70/30 brass—is the industry standard for these applications.
What Defines 260 Brass?
The performance of 260 brass is rooted in its simple but carefully controlled chemistry and its response to cold working. It is designed to be shaped, not machined, and its properties are tailored for forming operations.
What Is in the Alloy?
The chemical composition of 260 brass is defined by its copper and zinc content, with strict limits on other elements to ensure consistency and safety.
| Element | Content Range (%) | Its Role in the Alloy |
|---|---|---|
| Copper (Cu) | 68.5 – 71.5 | Provides strength, ductility, and the characteristic warm, golden color. |
| Zinc (Zn) | Remainder (approx. 29%) | Enhances formability and reduces material cost. |
| Lead (Pb) | ≤ 0.07 | Kept very low to meet RoHS compliance standards for safety in consumer products. |
| Iron (Fe) | ≤ 0.05 | Minimized to prevent brittleness during forming. |
A leading ammunition manufacturer in Colorado relies on 260 brass for its cartridge cases. They choose it because its high ductility allows the case to stretch under pressure without cracking during firing, while its strength ensures it holds its shape. The low lead content also makes the spent casings safer for the environment.
What Are Its Key Mechanical and Physical Properties?
260 brass’s properties are highly dependent on its temper, which is controlled by the amount of cold work applied.
| Property | Annealed (Soft) | Cold-Worked (Hard) | Why This Matters |
|---|---|---|---|
| Tensile Strength | 300 – 360 MPa | Up to 500+ MPa | Strong enough for applications like radiator cores and ammunition casings. |
| Yield Strength | 75 – 150 MPa | 280 – 400 MPa | Low yield strength in the annealed state makes it easy to form; cold working hardens it for final strength. |
| Elongation | 66% | 5 – 15% | Exceptional ductility. It can stretch to nearly twice its original length before breaking, ideal for deep drawing. |
| Hardness | 55 – 70 HRB | 80 – 100 HRB (Spring Temper) | Soft for forming; can be work-hardened to a spring temper for parts like clips. |
| Density | 8.53 g/cm³ | 8.53 g/cm³ | Heavier than aluminum, lighter than steel, providing a solid feel for decorative items. |
| Electrical Conductivity | 28% IACS | 28% IACS | Adequate for electrical applications like socket shells and terminals. |
| Annealing Temperature | 427 – 482°C | N/A | Heating to this range softens the metal after cold work, restoring its formability. |
How Is 260 Brass Formed and Shaped?
260 brass is renowned for its exceptional cold working and formability. It is one of the most formable brasses available, making it the go-to choice for operations that involve significant shaping without heat.
Deep Drawing and Stamping
This is where 260 brass truly excels.
- Deep Drawability: It can be pulled into deep, thin-walled shapes like ammunition casings, small bowls, and radiator tanks without cracking. Its high elongation (66%) allows for multiple drawing steps.
- Stamping: It is ideal for stamping complex shapes like electrical socket shells, decorative trim, and jewelry components. The metal flows well under pressure, filling intricate die details.
- Minimal Earing: It exhibits very little “earing”—the small bumps that can form on the edge of drawn parts. This reduces the need for costly trimming and finishing operations.
Work Hardening and Annealing
As 260 brass is formed, it work-hardens. This means it becomes stronger and harder with each shaping operation. While this is useful for achieving final strength, it can also make the metal too brittle to continue forming. To solve this, the metal is annealed. It is heated to 427-482°C and then cooled. This process softens the metal, restoring its ductility so it can be shaped further.
A musical instrument maker uses this process to create trumpet tubes. They roll-form the brass into long, curved shapes. As the metal work-hardens, they anneal it to keep it flexible enough to be bent into the instrument’s unique, complex design.
Where Is 260 Brass Used?
The combination of formability, strength, and attractive appearance makes 260 brass a staple across many industries.
Ammunition and Automotive
- Cartridge Cases: This is the classic application. The 70/30 brass balance provides the perfect combination of strength to contain the explosion and ductility to expand and seal the chamber.
- Radiator Cores and Tanks: A radiator manufacturer uses 260 brass for its radiator cores. Its high elongation allows them to form thin, complex tubes, while its thermal conductivity helps transfer heat efficiently.
- Electrical Connectors: Its good conductivity and formability make it suitable for terminals and connectors.
Decorative and Consumer Goods
- Jewelry: A jewelry brand in California makes affordable wedding bands from 260 brass. They stamp the metal into rings, polish it to a bright gold shine, and coat it with a protective layer to prevent tarnishing—all at a fraction of the cost of gold.
- Lamp Fixtures and Decorative Trim: Its warm color and ability to be formed into intricate shapes make it a popular choice for lighting and architectural accents.
- Musical Instruments: Trumpets, trombones, and tubas rely on 260 brass for their tubes and bells. It produces a warm tone and bends easily into the required shapes.
Industrial Applications
- Heat Exchanger Tubes: Its high thermal conductivity and corrosion resistance to water make it suitable for heat exchangers.
- Flexible Hoses: Its ductility allows it to be formed into corrugated, flexible hoses that can handle bending without cracking.
How Does 260 Brass Compare to Other Alloys?
Choosing the right material often means comparing 260 brass to its alternatives. The table below provides a clear breakdown.
| Alloy | Formability | Machinability | Lead Content | Relative Cost | Best Application |
|---|---|---|---|---|---|
| 260 Brass (C26000) | Excellent (100%) | 65% (Fair) | <0.07% (RoHS) | 100% (Baseline) | Formed parts: stampings, deep-drawn components, jewelry |
| 360 Brass (C36000) | 40% (Poor) | Excellent (100%) | 3.1% (High) | 100% | Machined parts: fittings, valves, gears |
| 110 Copper | 80% (Good) | 40% (Fair) | 0% | 120-150% | Electrical components requiring maximum conductivity |
| 304 Stainless Steel | 30% (Poor) | 30% (Poor) | 0% | 150-200% | Corrosive environments, outdoor parts, high-strength applications |
| 5052 Aluminum | 90% (Very Good) | 50% (Fair) | 0% | 50-70% | Lightweight formed parts, automotive trim |
Analysis: For a deep-drawn part like a radiator tank or an ammunition casing, 260 brass is the superior choice due to its unmatched formability. For a part that requires extensive machining, like a threaded valve fitting, the free-machining 360 brass is a better option. For an outdoor component exposed to saltwater, stainless steel would be more appropriate.
260 brass is a material defined by its exceptional formability. Its 70% copper, 30% zinc composition provides a unique combination of high ductility and good strength, allowing it to be stamped, deep-drawn, and formed into complex shapes that other metals cannot achieve. Its bright, gold-like appearance and ability to take a high polish make it equally valued for decorative applications. While it is not the best choice for machining or for highly corrosive environments, its performance in forming operations is unmatched. For any project that requires intricate shaping, a warm aesthetic, and reliable performance, 260 brass is a proven, cost-effective, and versatile solution.
How to write a spec that gets priced correctly
A drawing is a contract. If it leaves a number open, the shop fills that number in with its own default. The default is rarely the one you had in mind. Put these five lines on every RFQ and most of the back-and-forth disappears before it starts.
- Alloy designation and the standard behind it
- Temper or heat treatment condition
- Mechanical properties you actually need
- Mill certificate and traceability requirement
- Finish and the faces it applies to
The point is not paperwork. Each line removes a decision the shop would otherwise make for you. A complete RFQ comes back priced. An incomplete one comes back guessed.
What actually drives the price
Buyers usually push on material because it is the line they can see. In practice the material is rarely the biggest number on a quote. These five lines decide most of it:
- alloy grade and mill availability
- stock size versus finished size
- heat treatment and testing
- machinability
- certification
Ask for the quote split by line. A supplier who cannot break it down is guessing, and you will pay for the guess. The line you can usually renegotiate is the tolerance band, not the raw material.
Problems you will meet, and the fix
Every process has a failure mode it prefers. The same four show up again and again on this kind of work, and none of them are mysteries once you know what to look for.
- Substituting a similar grade without telling anyone
- Hardness that varies across a single bar
- Corrosion in a weld heat-affected zone
- Distortion after heat treatment on a thin part
Catch the fault on the first part, not the hundredth. A first-article check costs an hour. A bad batch costs the whole order. Write the check into the purchase order so nobody has to remember it.
What to check on the first article
The first article is the cheapest inspection you will ever buy. Use it properly and the rest of the run becomes boring, which is exactly what you want.
- Every dimension on the drawing, with the measured value written beside it.
- The material certificate, matched to the heat or lot number on the parts.
- The finish against the sample you approved, under the same light.
- Fit against the mating part, assembled rather than measured.
- Packaging, because parts that arrive damaged were never in tolerance.
Check in this order: datums, then mating features, then cosmetic faces. If the datums are wrong, every number after them is noise. Keep the report on file. When a problem shows up in month six, that document is the only thing that tells you what changed.
How to compare two quotes fairly
Two numbers are not comparable unless the scope matches. Line them up before you decide, because a low number with three gaps is not a low number.
Same drawing, same material, same finish, same inspection. Anything else is a different job wearing the same part number. Then look at what each quote leaves out. Freight, packaging, certificates and tooling are the usual gaps.
Ask each supplier to state their assumptions in writing. The one who does is usually the one who has run the process before.
Scaling from one part to a batch
The first part teaches you the process. The hundredth teaches you the process cost.
Watch three things as volume grows: setup amortisation, tool wear, and how much hand work the finish still needs. If the unit price barely moves between ten and a hundred, the cost sits in material or in hand work, not in setup. Ask which, because only one of them is negotiable.
Lead time behaves the same way. A one-off is scheduled around other jobs. A repeat order is scheduled around your forecast. Give the shop a forecast and the lead time gets shorter, not longer.
How to read a supplier's quote
A quote is a short document with a long shadow. Four things in it decide whether the job runs smoothly, and only one of them is the price.
- The scope line. It should name the process, the material and the finish, not just the part.
- The tolerance basis. General tolerance or the drawing, and which standard it follows.
- The exclusions. Tooling, freight, certificates and inspection are the usual omissions.
- The validity date. Material prices move, and an open-ended quote is a promise nobody can keep.
Read the exclusions before you read the total. A quote that leaves out tooling is not cheaper. It is a quote for a different job.
What to send with the first order
The first order sets the pattern for every order after it. Send a complete package once and the shop files it, and the second order takes a fraction of the time.
- A STEP or native model plus a PDF drawing carrying the same revision letter.
- The material callout by standard number, not by trade name.
- The finish and the exact faces it applies to.
- Any test the part must pass: fit, seal, drop, salt spray, dielectric.
- A contact who can answer a question inside one working day.
Then write down what was agreed. An email that confirms the material, the finish and the date is worth more than a longer purchase order that leaves them open.
When this is the wrong choice
A good supplier tells you when the process does not fit. These are the cases where we say so.
- The volume is so low that setup costs more than the parts are worth.
- The tolerance is tighter than the process can hold without a second operation.
- The geometry cannot be made without a tool feature that will not pay back.
- The material you need is not available in the form the process requires.
- The schedule is shorter than the tooling or setup time, and nobody has said so yet.
None of these are refusals. They are reasons to look at a different route, and the earlier that conversation happens the cheaper it is. The most expensive mistake in manufacturing is a process chosen before the question was understood.
Planning the ramp from prototype to production
The gap between one good part and a thousand identical ones is a plan, not a machine. Three decisions close it.
First, freeze the design. Every change after tooling starts is a re-cut, and re-cuts are where schedules go. Second, decide the inspection level. A prototype is checked by eye; a production part is checked against a report. Third, agree the change process in writing, including who pays for it.
Write the ramp down as dates and owners, not as intentions. A ramp plan with three names and three dates is worth more than a page of good intentions.
What documentation to expect
Paperwork is not bureaucracy when a part fails at the customer. It is the only record of what was agreed. A normal shipment should carry four documents.
- A dimensional report covering every callout on the drawing.
- A material certificate traceable to the heat or lot number.
- A finish or coating certificate where the specification requires one.
- A packing list that matches the carton labels.
If a supplier cannot produce these on request, they are not running a controlled process. Ask for one sample set before you place the first order and you will know exactly what you are buying.
Our solution for 260 Brass (C26000)
YiguProto runs metal sourcing and machining in house, from a single prototype to a production batch. We quote the process, the material and the finish as separate lines, so you can see where the money goes instead of arguing with one number.
Send a STEP file or a drawing and you get a DFM report in one to two business days. It flags the features that add cost and the features that will not hold tolerance on the process you picked.
Every order ships with an inspection report on the features you call out. If a part misses, we make it again. Ready to price a part? Start with a free quote and DFM review, or read more about our metal sourcing and machining. You can also talk to an engineer before you commit to a drawing.
FAQ about 260 Brass (C26000)
What material should I specify?
Specify by standard, not by trade name. A trade name can change under you between two orders; a standard number cannot. Then add the one property that actually decides the part, whether that is strength, heat resistance or chemical exposure.
What is the lead time for 260 Brass (C26000)?
Expect 5 to 12 business days depending on mill stock. Tooling, material stock and the finishing queue all move that number, so we confirm the date in writing before the run starts rather than after.
What files do you need in order to quote?
A STEP file plus a PDF drawing that carries the same revision letter. The model carries the geometry and the drawing carries the intent. When the two disagree, the shop picks one, and it is never the one you meant.
What is 260 Brass (C26000) used for?
260 Brass (C26000) turns up wherever the part has to do a real job at a predictable cost: brackets, housings, fixtures, covers and the fittings that hold them together. The honest test is whether the properties match the load and the environment, not whether the material is fashionable.
How much does 260 Brass (C26000) cost?
Price comes from five lines: material, machine or tool time, setup, finishing and inspection. The material itself is usually the smallest of them. Send a drawing and we will split the quote so you can see which line is doing the damage.
How long does a first article take?
Usually a few business days once the drawing is frozen, and longer if tooling is involved. The date we give you is the date we confirm in writing, not the date we hope for.
The short version
260 Brass (C26000) rewards the buyer who reads the data sheet and the drawing together. Pick the option for the property that matters, not for the price per kilo.
Tighten only what mates. Test a sample before the run. Then let the process do the rest.