Material densities

The density of every material a mass check reads, each quoted from the page that states it.

The model

Every mass check in the catalogue rests on one relation: mass is density times volume. A cartridge's case is brass of a known density, a pistol's frame is steel or polymer, a bullet's core is lead. The registry holds each material's density with the page that states it, and the checks read it from there.

m = ρ V

1 g / {cm}^{3} = 1 mg / {mm}^{3} = 1000 kg / m^{3}

m_{part} = φ V_{box} ρ_{material}

where

$ρ$: the material's density, from the registry
$V$: the volume the material fills
$φ$: the fill fraction: the share of the bounding box the material fills (a steel pistol about 13%)

A density enters the registry only with a page that states it, quoted in the page's own words, and the materials check reads every page again each run. A figure for a class of material (stainless steel) covers its grades with a range (304, 416 and 17-4 PH run from 7.7 to 8.0 g/cm³), and the checks allow for it.

Each material also carries what it is made of: its elements by mass for its typical grade, as the standard or datasheet states them, with the base metal marked balance. The materials check reads those pages again too.

Carbon and alloy steel: the quoted density should fall in the range the registry declares

7.75 g/cm³7.90 g/cm³quoted: 7.85 g/cm³

Answer: 7.85 g/cm³ lies inside 7.75 to 7.9, so the source and the range agree.

The registry

Material	Density	Composition
Leadpure, antimony-hardenedbullet-core, bullet pure: en.wikipedia.org	11.348g/cm³10.9 to 11.35	82PbLead100% By mass, pure
Copperpurebullet, bullet-jacket pure: en.wikipedia.org	8.935g/cm³8.9 to 8.96	29CuCopper100% By mass, pure
BronzeC93200frame, receiver C93200: makeitfrom.com	8.8g/cm³8.7 to 8.9	29CuCopper81–85% 82PbLead6–8% 50SnTin6.3–7.5% 30ZnZinc2–4% By mass, UNS C93200
Gilding metalUNS C21000 (95/5)bullet-jacket C21000: makeitfrom.com	8.8g/cm³8.75 to 8.86	29CuCopper94–96% 30ZnZinc3.7–6% By mass, UNS C21000
Cartridge brassUNS C26000 (70/30)case, receiver C26000: azom.com	8.53g/cm³8.5 to 8.55	29CuCopper68.5–71.5% 30ZnZinc28.5% 82PbLead≤ 0.07% 26FeIron≤ 0.05% By mass, UNS C26000
Nickel silver (German silver)UNS C75200 (65-18)frame, grip C75200: makeitfrom.com	8.5g/cm³8.5 to 8.5	29CuCopper63.5–66.5% 30ZnZinc12.7–20% 28NiNickel16.5–19.5% 25MnManganese≤ 0.5% By mass, UNS C75200
Stainless steel304, 416, 17-4 PHframe, slide, barrel, receiver, attachment 304: en.wikipedia.org 17-4 PH: en.wikipedia.org 416 (barrels): makeitfrom.com	7.9g/cm³7.7 to 8	26FeIronbalance 24CrChromium18–20% 28NiNickel8–11% 25MnManganese≤ 2% 14SiSilicon≤ 1% 6CCarbon≤ 0.08% By mass, 304
Ironwrought, castframe, barrel, receiver pure: en.wikipedia.org	7.874g/cm³7 to 7.874	26FeIron100% By mass, pure
Carbon and alloy steelAISI 4140, AISI 4150, 1018, chrome-molyframe, slide, barrel, receiver, magazine, attachment AISI 4140: azom.com	7.85g/cm³7.75 to 7.9	26FeIronbalance 24CrChromium0.8–1.1% 25MnManganese0.75–1% 6CCarbon0.38–0.43% 14SiSilicon0.15–0.3% 42MoMolybdenum0.15–0.25% By mass, AISI 4140
Zinc alloy (Zamak)Zamak 3frame, slide Zamak 3: en.wikipedia.org	6.6g/cm³6.6 to 6.7	30ZnZincbalance 13AlAluminium3.9–4.3% 29CuCopper≤ 0.1% 12MgMagnesium0.025–0.05% By mass, Zamak 3 (ASTM B240 ingot)
Titanium alloyTi-6Al-4V (grade 5)frame, slide, barrel, attachment Ti-6Al-4V: en.wikipedia.org	4.43g/cm³4.42 to 4.5	22TiTitaniumbalance 13AlAluminium5.5–6.75% 23VVanadium3.5–4.5% By mass, Ti-6Al-4V
Aluminium alloy6061-T6, 7075-T6frame, receiver, slide, stock, attachment 6061: en.wikipedia.org 7075: en.wikipedia.org	2.75g/cm³2.7 to 2.81	13AlAluminium95.85–98.56% 12MgMagnesium0.8–1.2% 14SiSilicon0.4–0.8% 26FeIron≤ 0.7% 29CuCopper0.15–0.4% 24CrChromium0.04–0.35% By mass, 6061
Bonegrip engineeringtoolbox.com	1.85g/cm³1.7 to 2
Glass-fibre composite (fibreglass, G-10)G-10 / FR-4, E-glass fabric in epoxystock, grip, frame FR-4: en.wikipedia.org fibreglass: en.wikipedia.org	1.85g/cm³1.5 to 2.5
Ivorygrip engineeringtoolbox.com	1.85g/cm³1.8 to 1.9
Magnesium alloycast alloysframe, receiver en.wikipedia.org	1.8g/cm³1.8 to 1.8
Carbon fibre compositestandard-modulus fabric in epoxy, M55 unidirectionalstock, frame, barrel, attachment Std CF fabric: performance-composites.com	1.6g/cm³1.6 to 1.65
Glass-filled nylon (polymer)PA66 GF30frame, stock, magazine, attachment PA66 GF30: ensingerplastics.com composition: en.wikipedia.org	1.36g/cm³1.34 to 1.48	(C₁₂H₂₂N₂O₂)_nNylon 66balance Glass fibre30% By mass, PA66 GF30
Bakelite (phenolic)phenol formaldehydestock, grip en.wikipedia.org engineeringtoolbox.com	1.3g/cm³1.3 to 1.36
Hard rubber (ebonite, vulcanite)ebonitegrip, stock ebonite: engineeringtoolbox.com hard rubber: engineeringtoolbox.com composition: en.wikipedia.org	1.15g/cm³1.1 to 1.2	(C₅H₈)_nNatural rubberbalance Sulfur and linseed oil25–80% By mass, ebonite
Nylon 66 (unfilled)PA66, Zytel 101frame, stock Zytel: en.wikipedia.org	1.14g/cm³1.13 to 1.15	(C₁₂H₂₂N₂O₂)_nNylon 66100% By mass, PA66
Rubber (soft)soft commercial, pure gumstock, grip soft commercial: engineeringtoolbox.com pure gum: engineeringtoolbox.com	1.1g/cm³0.91 to 1.1
EbonyGaboon ebonygrip, stock Gaboon ebony: wood-database.com composition: en.wikipedia.org	0.955g/cm³0.955 to 0.955	6CCarbon50% 8OOxygen42% 1HHydrogen6% 7NNitrogen1% By mass, wood in generalThe elemental make-up of wood, which varies little between species; the source gives it for wood, not for this species.
Leatherdrystock, grip dry: engineeringtoolbox.com	0.86g/cm³0.86 to 0.86
RosewoodEast Indian rosewood, cocobolostock, grip East Indian rosewood: wood-database.com cocobolo: wood-database.com composition: en.wikipedia.org	0.855g/cm³0.855 to 1.095	6CCarbon50% 8OOxygen42% 1HHydrogen6% 7NNitrogen1% By mass, wood in generalThe elemental make-up of wood, which varies little between species; the source gives it for wood, not for this species.
BeechEuropean beechstock European beech: wood-database.com composition: en.wikipedia.org	0.71g/cm³0.65 to 0.75	6CCarbon50% 8OOxygen42% 1HHydrogen6% 7NNitrogen1% By mass, wood in generalThe elemental make-up of wood, which varies little between species; the source gives it for wood, not for this species.
Maplehard maplestock hard maple: wood-database.com composition: en.wikipedia.org	0.705g/cm³0.705 to 0.705	6CCarbon50% 8OOxygen42% 1HHydrogen6% 7NNitrogen1% By mass, wood in generalThe elemental make-up of wood, which varies little between species; the source gives it for wood, not for this species.
Birchyellow birchstock yellow birch: wood-database.com composition: en.wikipedia.org	0.69g/cm³0.69 to 0.69	6CCarbon50% 8OOxygen42% 1HHydrogen6% 7NNitrogen1% By mass, wood in generalThe elemental make-up of wood, which varies little between species; the source gives it for wood, not for this species.
WalnutAmerican black walnutstock, grip black walnut: wood-database.com composition: en.wikipedia.org	0.61g/cm³0.55 to 0.7	6CCarbon50% 8OOxygen42% 1HHydrogen6% 7NNitrogen1% By mass, wood in generalThe elemental make-up of wood, which varies little between species; the source gives it for wood, not for this species.

Each material also lists the catalogue values it covers (steel, carbon_steel, chromoly_steel and the rest are carbon steel), so a record's frame material finds its density whatever it is called.

Checks that use this method

Findings this method raised

Every task the 5 checks resting on this method put on the review queue, open and closed, with where each one stands.

Reading the findings…

Task	Record	Check	Status	Opened	Closed