Talk to a firearm alloy expert
Alloys at home on the range and in the field
Long-range precision
Materials you can count on
Carpenter Technology has been producing superior firepower since our armor-piercing alloys helped win the Spanish-American war in 1889. Our legacy alloys and novel chemistries continue that tradition, offering manufacturers an exclusive strategic advantage.
Performance alloys
Proven industry standards
High-quality materials built to perform under the most extreme conditions:
Performance alloys
Explore firearm alloys
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A-421™: High strength, ductility, hardness,
and corrosion resistance
A-21® is the first and only truly stainless carburizing steel. Repels rust and delivers industry-leading corrosion resistance and toughness without compromising strength.
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Legacy alloys trusted by manufacturers year after year:
Carpenter 158: Case hardening chrome-nickel alloy steel with maximum strength
416 family: Martensitic, free-machining stainless
steels with high hardness
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TALK TO AN EXPERT
performance alloys
proven industry standards
CHAT WITH A WEAPONRY
ALLOY EXPERT
CHAT WITH A WEAPONRY
ALLOY EXPERT
More: 410 Modified, 420, 440C, 4330V, Custom 630,
VAR 9310
Materials engineered for
premium firearms
A-21®
Advanced martensitic stainless steel for bolts and barrels
Strong, tough, and stainless at any temperature.
A-21® stainless carburizing steel was designed for bolt applications that require a hard, stainless case and a strong, tough, ductile core, as well as barrel applications that need high strength and toughness, long life, and excellent corrosion resistance. A-21® is an upgrade in corrosion resistance and toughness at similar strength levels relative to 410 MODIFIED and 416 MOD low sulfur steels.
A-421™
Ultra-high strength stainless steel for precision firearm parts and blades
Hard, strong, rust-free. A-421™ is a quenched and tempered martensitic stainless steel engineered for critical firearm components and blades with excellent edge retention. It can be heat treated for ultra-high strength or high hardness (60+ HRC), with ductility and outstanding corrosion resistance in either condition. A-421™ remains rust-free after 200 hours of salt fog exposure, an upgrade over 440C and other stainless steels at similar hardness.
Tried-and-true alloy solutions
Proven industry standards
410 MODIFIED
Stainless steel for revolver cylinders and gun barrels
Can take the heat. 410 MODIFIED is a hardenable martensitic stainless steel suitable for highly stressed parts where corrosion resistance, good strength,
and ductility are needed. This alloy can be used up
to 1200°F (649°C) where resistance to scaling and oxidation is required.
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American made.
Best in the trade.
CARPENTER 158
Case-hardened steel for rifle bolts
Hard core strength. Carpenter 158 is a chrome-nickel alloy steel engineered for parts subject to heavy shock and wear. Fully treated, Carpenter 158 attains a core strength of approximately 160 ksi (1103 MPa) tensile strength with a yield point of approximately
135 ksi (931 MPa).
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High-quality
alloys
More: Custom 465®, AerMet® 100, NiMark® 250,
NiMark® 300, Vacumet 1.4418
The alloys you need — lock, stock, and barrel
Fire with confidence
• A-21®
• Carpenter 158
• Custom 465®
• 9310
Bolts & bolt carriers:
More novel chemistries
Custom 465®: Premium melted, martensitic, age-hardenable stainless steel. Designed to have excellent notch tensile strength and fracture toughness in the overaged (H 950) condition.
2
AerMet® 100: Alloy with high hardness and strength combined with exceptional ductility, toughness, and stress corrosion cracking resistance.
NiMark® 250: Low-carbon, nickel-cobalt-molybdenum high-temperature alloy capable of yield strength in excess of 240 ksi.
VACUMET 1.4418: Formulated for applications requiring high mechanical strength with improved corrosion resistance relative to traditional martensitic stainless steels.
NiMark® 300: Similar to NiMark 250, but capable of yield strength in excess of 270 ksi.
416
Stainless steel for revolver, rifle, and pistol components
Built to last. Carpenter Technology metallurgists invented 416 in 1924. The first free-machining stainless steel, 416 had — and still has — an enormous impact on global manufacturing. The addition of sulfur to this high-chromium, corrosion-resisting steel gives it easy machining properties, and the original formulation of 416 is still being made and used today.
For advanced weaponry, 416 Modified Low Sulfur is specified for rifle barrels and pistol slides, while 416 Forge Quality is ideal for revolver frames.
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More legacy alloys
Custom 630 (17-4): Martensitic precipitation hardening stainless steel with high strength and hardness, as well as excellent corrosion resistance.
420: Hardenable 12% chrome steel with high strength at room and moderately elevated temperatures and mirror-like finishes without chrome plating.
440C: High-carbon chromium steel designed to provide stainless properties with maximum hardness.
4330V: Low alloy steel capable of being heat treated to high strength levels. Particularly useful in applications involving shock loading or stress concentration.
9310: Premium quality chromium-nickel-molybdenum carburizing steel with high hardenability and core hardness, plus superior fatigue strength.
• A-421™
• Custom 630 (17-4)
Suppressors
& shotgun chokes:
• 410
• 416
Receivers:
• A-421™
• Custom 465®
Firing pins & springs:
Download the A-21 PRESENTATION
Download the firearm presentation
Download the A-421 PRESENTATION
• A-21®
• GNB200
• 1.4418
• 410
• 416
Barrels & barrel extensions: