303 — Machining & Properties
Typical properties, what 303 is like on a machine tool, what it gets used for, and the tolerance and finishes we hold on it — from a shop that actually machines it, not a datasheet aggregator. Every figure here drives our own calculators.
Machining 303
Machinability is rated good — a well-behaved material to machine with correctly chosen tooling and parameters. Austenitic grades (303, 304, 316) work-harden during cutting. Sharp tooling, correct feeds and speeds, and no dwelling are essential. Martensitic and PH grades should be machined in the annealed condition where possible, with final heat treatment applied post-machining to minimise distortion.
Our standard achievable tolerance on 303 is ±0.010mm under normal conditions, with tighter tolerances on critical features agreed at quotation. Standard finishes: As machined, passivation. Full material traceability with MTR and CoC documentation on every order.
Typical applications
Shafts, connectors, turned fittings, bolts and studs.
Use 303 in our free tools
Other stainless steel grades we machine: 304 / 304L · 316 / 316L · 17-4 PH (630) · 15-5 PH — all 50 grades.
303 — FAQ
What is the density of 303?
7.9 g/cm³ (typical). That is 7900 kg/m³ — our metal weight calculator uses exactly this figure for 303.
What is the tensile strength of 303?
Typically 620 MPa. Treat it as a typical value, not a specification — the Material Test Report supplied with your order states the actual certified figures for the batch.
Is 303 easy to machine?
Its machinability is rated good — a well-behaved material to machine with correctly chosen tooling and parameters.
What is 303 used for?
Typical applications: Shafts, connectors, turned fittings, bolts and studs.
What tolerance can be held when machining 303?
Our standard achievable tolerance on 303 is ±0.010mm under normal conditions (ISO 2768-f general tolerancing). Tighter tolerances on critical features can be agreed at quotation for specific geometries.
Can Dalloway machine 303?
Yes — we machine 303 in-house on 3, 4 and 5-axis milling and CNC turning, from single prototypes to production, with MTR and CoC documentation standard. Typical finishes: As machined, passivation.
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