Ammunition

• X-API-Keystringheaderrequired

  Your API key. Authorization: Bearer <key> is accepted in its place.

• idstringrequired

  Resource slug ID

  Accepts

  a lowercase slug: letters, digits and hyphens

  Example

  glock-g17-gen5

The example asks for glock-g17-gen5. See that record on gunspec.io, rendered for people.

• ammo_idstringrequired

  Ammunition load to fire

  Max length

  255

  Example

  m882

• dataobject

  Muzzle solution adjusted for this firearm barrel length, against its published figures.

• data.firearmBallisticsFirearm

  The firearm the solution was computed for. barrelLengthMm is absent when the firearm has no recorded barrel.

• data.firearm.idstring

  URL-safe slug identifying the firearm, e.g. glock-g17-gen5.

• data.firearm.namestring

  Display name, as the maker writes it.

• data.firearm.barrelLengthMmnumber

  Barrel length in millimetres, measured from the breech face.

• data.ammunitionobject

  The load the calculation used.

• data.ammunition.idstring

  Slug of the ammunition load that was fired.

• data.ammunition.namestring

  Display name, as the maker writes it.

• data.calculatedobject

  The figures derived for the barrel length asked about, rather than the reference one.

• data.calculated.muzzleVelocityMpsnumber

  Muzzle velocity in metres per second, for the default load.

• data.calculated.muzzleEnergyJnumber

  Muzzle energy in joules, for the default load.

• data.calculated.terminalBallisticsTerminalBallistics

  Terminal performance indices computed at the muzzle.

• data.sourceReportedobject

  The figures published for this firearm, where the catalog records them.

• data.sourceReported.muzzleVelocityMpsnumber | null

  Muzzle velocity in metres per second, for the default load.

• data.sourceReported.muzzleEnergyJnumber | null

  Muzzle energy in joules, for the default load.

• data.deltaobject

  Computed minus source-reported. Null where no source figure exists to compare against.

• data.delta.velocityMpsnumber | null

  Remaining velocity at this distance, in metres per second.

• data.delta.energyJnumber | null

  Remaining energy at this distance, in joules.

• data.errorstring | null

  Why the calculation could not be completed, or null when it succeeded.

• 400VALIDATION_ERRORValidation error
• 401UNAUTHORIZEDAPI key required
• 403FORBIDDENValid key, not permitted
• 404NOT_FOUNDResource not found
• 429RATE_LIMITEDRate limit exceeded
• 500INTERNAL_ERRORUnexpected server error

• X-API-Keystringheaderrequired

  Your API key. Authorization: Bearer <key> is accepted in its place.

• idstringrequired

  Resource slug ID

  Accepts

  a lowercase slug: letters, digits and hyphens

  Example

  glock-g17-gen5

The example asks for glock-g17-gen5. See that record on gunspec.io, rendered for people.

• ammo_idstring

  Ammunition load to chamber. Defaults to the firearm default load, then the first common load for its primary caliber.

  Max length

  255

  Example

  m882

• zero_minteger

  Zero distance in metres, where the bullet crosses the line of sight. Defaults to 25 for a handgun and 100 for a long gun.

  Range

  10 – 1000

  Example

  25

• sight_height_mmnumber

  Line of sight above the bore, in mm. Defaults to 20 for a handgun and 38 for a long gun.

  Range

  0 – 150

  Example

  20

• dataobject

  The response payload.

• data.firearmBallisticsFirearm

  The firearm the solution was computed for. barrelLengthMm is absent when the firearm has no recorded barrel.

• data.firearm.idstring

  URL-safe slug identifying the firearm, e.g. glock-g17-gen5.

• data.firearm.namestring

  Display name, as the maker writes it.

• data.firearm.barrelLengthMmnumber

  Barrel length in millimetres, measured from the breech face.

• data.ammunitionobject

  The load the calculation used.

• data.ammunition.idstring

  Slug of the ammunition load the firearm was chambered with.

• data.ammunition.namestring

  Display name, as the maker writes it.

• data.ammunition.caliberIdstring

  Slug of the cartridge. Resolve against /v1/calibers/{id}.

• data.ammunition.bulletWeightGnumber

  Bullet weight in grams. Divide by 0.0648 for grains.

• data.ammunition.bulletTypestring

  Bullet construction: fmj, jhp, sp, match.

• data.calculatedobject

  The figures derived for the barrel length asked about, rather than the reference one.

• data.calculated.muzzleVelocityMpsnumber

  Muzzle velocity in metres per second, for the default load.

• data.calculated.muzzleEnergyJnumber

  Muzzle energy in joules, for the default load.

• data.calculated.effectiveRangeMnumber

  Effective range in metres against a point target.

• data.calculated.terminalBallisticsTerminalBallistics

  Terminal performance indices computed at the muzzle.

• data.sourceReportedobject

  The figures published for this firearm, where the catalog records them.

• data.sourceReported.muzzleVelocityMpsnumber | null

  Muzzle velocity in metres per second, for the default load.

• data.sourceReported.muzzleEnergyJnumber | null

  Muzzle energy in joules, for the default load.

• data.sourceReported.effectiveRangeMnumber | null

  Effective range in metres against a point target.

• data.zeroingZeroing

  How the gun is assumed sighted for pathCm. Neither figure is recorded per gun, so each is an assumption the caller may override with zero_m and sight_height_mm: a handgun zeroed at 25 m with its sights 20 mm above the bore, a long gun at 100 m with an optic 38 mm above it.

• data.zeroing.zeroMnumber

  The distance at which the bullet crosses the line of sight, in m.

• data.zeroing.sightHeightMmnumber

  The line of sight above the bore, in mm.

• data.trajectoryTrajectoryPoint[]

  The flight path, one row per distance step.

• data.trajectory[].distanceMnumber

  Distance from the muzzle in metres.

• data.trajectory[].velocityMpsnumber

  Remaining velocity at this distance, in metres per second.

• data.trajectory[].energyJnumber

  Remaining energy at this distance, in joules.

• data.trajectory[].dropCmnumber

  Drop below the bore line at this distance, in cm: the fall under gravity alone, with no sighting.

• data.trajectory[].pathCmnumber

  Height relative to the line of sight at this distance, in cm, negative below: how a drop table reads, for the answer's zeroing (the gun zeroed at zeroM with its sights sightHeightMm above the bore). Starts at minus the sight height at the muzzle and is 0 at the zero.

• data.trajectory[].timeOfFlightSnumber

  Time of flight to this distance, in seconds.

• data.trajectory[].machNumbernumber

  Velocity as a multiple of the speed of sound. Below ~1.2 the projectile is transonic and destabilises.

• data.trajectory[].momentumKgMsnumber

  Momentum in kilogram-metres per second.

• data.trajectory[].tkoFactornumber

  Taylor Knock-Out factor at this distance.

• data.trajectory[].energyDensityJCm2number

  Energy per unit frontal area, in joules per square centimetre.

• data.errorstring | null

  Why the calculation could not be completed, or null when it succeeded.

• 400VALIDATION_ERRORValidation error
• 401UNAUTHORIZEDAPI key required
• 403FORBIDDENValid key, not permitted
• 404NOT_FOUNDResource not found
• 429RATE_LIMITEDRate limit exceeded
• 500INTERNAL_ERRORUnexpected server error

• X-API-Keystringheaderrequired

  Your API key. Authorization: Bearer <key> is accepted in its place.

• idstringrequired

  Caliber slug

  Accepts

  a lowercase slug: letters, digits and hyphens

  Example

  9x19mm-parabellum

The example asks for 9x19mm-parabellum. See that record on gunspec.io, rendered for people.

• pageintegerdefault1

  Page number, from 1 to 10,000

  Range

  1 – 10000

  Example

  1

• per_pageintegerdefault20

  Items per page (max 100)

  Range

  1 – 100

  Example

  20

• dataAmmunitionLoad[]

  A specific factory ammunition load within a caliber.

• data[].idstring

  URL-safe slug identifying the load, e.g. 9mm-124gr-fmj.

• data[].caliberIdstring

  Slug of the cartridge. Resolve against /v1/calibers/{id}.

• data[].namestring

  Display name, as the maker writes it.

• data[].designationstring | null

  Military or standards designation for the load, e.g. M882.

• data[].manufacturerstring | null

  Who makes it.

• data[].countryOfOriginstring | null

  ISO 3166-1 alpha-2 code of where it was designed, e.g. AT.

• data[].bulletWeightGnumber

  Bullet weight in grams. Divide by 0.0648 for grains.

• data[].bulletTypestring

  Bullet construction: fmj, jhp, sp, match.

• data[].ballisticCoefficientG1number | null

  Ballistic coefficient against the G1 drag model, the convention for flat-based bullets.

• data[].ballisticCoefficientG7number | null

  Ballistic coefficient against the G7 drag model, which fits boat-tail rifle bullets better than G1.

• data[].referenceVelocityMpsnumber

  Muzzle velocity in metres per second at the reference barrel length below, not at the barrel of any particular firearm.

• data[].referenceBarrelLengthMmnumber

  Barrel length in millimetres the reference velocity was measured from. Velocity for another barrel is extrapolated from this pair.

• data[].sectionalDensitynumber | null

  Bullet mass divided by the square of its diameter. Higher penetrates better, all else equal.

• data[].yearIntroducedinteger | null

  Year it entered production or service. Null where the date is disputed or unknown.

• data[].isCommoninteger

  1 when the load is commonly stocked.

• data[].bulletSvgUrlstring | null

  Absolute URL of the rendered bullet diagram.

• data[].velocityRetentionExponentnumber | null

  Decay exponent used when extrapolating velocity to a barrel length other than the reference one.

• data[].descriptionstring | null

  Prose summary of the record, where one has been written.

• data[].isMilitaryinteger

  1 when the load is a military issue round.

• data[].createdAtstring

  When the record was first added, YYYY-MM-DD HH:MM:SS in UTC.

• data[].updatedAtstring

  When a field we serve last changed. Maintained by the database rather than by whatever wrote the row, so it moves for a corrected figure and does not move for a re-run of the seed. Before migration 0113 the seed rewrote every load on every run, and this said so.

• data[].sourcesstring[]

  Where the figures came from. Null on every load today: this family has somewhere to cite from and nothing cited yet, which the data quality page counts as a gap rather than hiding. Check a velocity against the maker until it is filled.

• data[].dataConfidencenumber | null

  How well specified the load is, on the same 0 to 1 scale as a firearm's. Null until there are sources behind it: a confidence figure with nothing supporting it looks like evidence and is not.

• data[].provenanceProvenance

  Where a record's figures came from and how far they have been checked, in one place. sources are the pages consulted; check a specific figure against those. sourceKinds says what each page is and bestSourceKind the strongest of them, on the hierarchy SourceKind defines: a maker or standards-body page is evidence for a figure, a retailer or forum page is evidence the item exists. dataConfidence is the 0 to 1 score set from what was actually sourced and never raised by hand. verifiedAt and verifiedFields say when a source was last read against the record and which fields it stated; null means the row is still seed knowledge. updatedAt and version are the same cache signals the record carries at the top level.

• data[].provenance.sourcesstring[]

  The pages consulted when the record was compiled, as an array. Check a specific figure against these rather than against dataConfidence.

• data[].provenance.sourceKindsobject[]

  What each cited page is, in sources order, on the SourceKind hierarchy. A host not in the source map is other, never guessed.

• data[].provenance.bestSourceKindSourceKind | null

  The strongest kind among the citations, or null when nothing is cited. manufacturer or standards_body means a figure can be checked against an authority; retailer or community alone means the record is still supported by copies of copies.

• data[].provenance.makerSourcestring | null

  The first cited page on the record's own manufacturer's website, or null when it cites none. A page on another maker's site does not count. Cited from the maker is not the same as checked against it: verifiedFields names the figures that were read against a source.

• data[].provenance.evidencestring

  How far the record's figures are backed, strongest first, for a badge: verified when at least one figure was read against a source (verifiedFields), maker when it cites a page on its own manufacturer's site (makerSource), authority when it cites a maker, standards body or government page, secondary when it cites only press, retailers, references or forums, none when it cites nothing. Derived from the fields beside it.

• data[].provenance.checksobject

  The checks the record has been through, on a single record's response only: every task the data agent (Redback) or a person was given about it, what each proposed, the pages it read, and whether a person accepted it. Nothing an agent proposes reaches the record until a person accepts it, so this is the trail behind verifiedFields. Who reviewed is not published; an agent's instance name is.

• data[].provenance.dataConfidencenumber | null

  The 0 to 1 score set from what was actually sourced, never raised by hand. See the confidence bands in the docs.

• data[].provenance.verifiedAtstring | null

  When a source was last read against this record. Null means the row is still seed knowledge.

• data[].provenance.verifiedFieldsstring[]

  Which fields the source stated, as an array. Everything else on a verified row is still unverified. Null where no source has been read.

• data[].provenance.specSourcestring | null

  Cartridges only: the page the drawing figures were taken from. Null on every other kind of record.

• data[].provenance.updatedAtstring

  When a served column last changed; the same value the record carries at the top level.

• data[].provenance.versionstring | null

  The record's content version, equal to the top-level version; equal versions mean equal data.

• data[].versionstring | null

  Opaque fingerprint of this record. It changes when and only when a field we serve changes, so a client holding the same value already has the record and need not fetch it. Equality is the only supported operation: do not parse it, and do not assume how it is computed. Null means the record has not been written since versioning began, not that it is unchanged.

• pagination.pagenumber

  Current page number

• pagination.per_pagenumber

  Items per page

• pagination.totalnumber

  Total matching records (Builder and above)

• 400VALIDATION_ERRORValidation error
• 401UNAUTHORIZEDAPI key required
• 403FORBIDDENValid key, not permitted
• 404NOT_FOUNDResource not found
• 429RATE_LIMITEDRate limit exceeded
• 500INTERNAL_ERRORUnexpected server error

• X-API-Keystringheaderrequired

  Your API key. Authorization: Bearer <key> is accepted in its place.

• pageintegerdefault1

  Page number, from 1 to 10,000

  Range

  1 – 10000

  Example

  1

• per_pageintegerdefault20

  Items per page (max 100)

  Range

  1 – 100

  Example

  20

• qstring

  Substring match on the load name, designation, maker or cartridge name

  Max length

  200

  Example

  federal

• caliber_idstring

  Filter by caliber slug

  Example

  9x19mm-parabellum

• bullet_typestring

  Filter by bullet construction

  Example

  fmj

• is_commoninteger

  Restrict to commonly stocked loads (1) or uncommon ones (0)

  Range

  0 – 1

  Example

  1

• dataAmmunitionLoad[]

  A specific factory ammunition load within a caliber.

• data[].idstring

  URL-safe slug identifying the load, e.g. 9mm-124gr-fmj.

• data[].caliberIdstring

  Slug of the cartridge. Resolve against /v1/calibers/{id}.

• data[].namestring

  Display name, as the maker writes it.

• data[].designationstring | null

  Military or standards designation for the load, e.g. M882.

• data[].manufacturerstring | null

  Who makes it.

• data[].countryOfOriginstring | null

  ISO 3166-1 alpha-2 code of where it was designed, e.g. AT.

• data[].bulletWeightGnumber

  Bullet weight in grams. Divide by 0.0648 for grains.

• data[].bulletTypestring

  Bullet construction: fmj, jhp, sp, match.

• data[].ballisticCoefficientG1number | null

  Ballistic coefficient against the G1 drag model, the convention for flat-based bullets.

• data[].ballisticCoefficientG7number | null

  Ballistic coefficient against the G7 drag model, which fits boat-tail rifle bullets better than G1.

• data[].referenceVelocityMpsnumber

  Muzzle velocity in metres per second at the reference barrel length below, not at the barrel of any particular firearm.

• data[].referenceBarrelLengthMmnumber

  Barrel length in millimetres the reference velocity was measured from. Velocity for another barrel is extrapolated from this pair.

• data[].sectionalDensitynumber | null

  Bullet mass divided by the square of its diameter. Higher penetrates better, all else equal.

• data[].yearIntroducedinteger | null

  Year it entered production or service. Null where the date is disputed or unknown.

• data[].isCommoninteger

  1 when the load is commonly stocked.

• data[].bulletSvgUrlstring | null

  Absolute URL of the rendered bullet diagram.

• data[].velocityRetentionExponentnumber | null

  Decay exponent used when extrapolating velocity to a barrel length other than the reference one.

• data[].descriptionstring | null

  Prose summary of the record, where one has been written.

• data[].isMilitaryinteger

  1 when the load is a military issue round.

• data[].createdAtstring

  When the record was first added, YYYY-MM-DD HH:MM:SS in UTC.

• data[].updatedAtstring

  When a field we serve last changed. Maintained by the database rather than by whatever wrote the row, so it moves for a corrected figure and does not move for a re-run of the seed. Before migration 0113 the seed rewrote every load on every run, and this said so.

• data[].sourcesstring[]

  Where the figures came from. Null on every load today: this family has somewhere to cite from and nothing cited yet, which the data quality page counts as a gap rather than hiding. Check a velocity against the maker until it is filled.

• data[].dataConfidencenumber | null

  How well specified the load is, on the same 0 to 1 scale as a firearm's. Null until there are sources behind it: a confidence figure with nothing supporting it looks like evidence and is not.

• data[].provenanceProvenance

  Where a record's figures came from and how far they have been checked, in one place. sources are the pages consulted; check a specific figure against those. sourceKinds says what each page is and bestSourceKind the strongest of them, on the hierarchy SourceKind defines: a maker or standards-body page is evidence for a figure, a retailer or forum page is evidence the item exists. dataConfidence is the 0 to 1 score set from what was actually sourced and never raised by hand. verifiedAt and verifiedFields say when a source was last read against the record and which fields it stated; null means the row is still seed knowledge. updatedAt and version are the same cache signals the record carries at the top level.

• data[].provenance.sourcesstring[]

  The pages consulted when the record was compiled, as an array. Check a specific figure against these rather than against dataConfidence.

• data[].provenance.sourceKindsobject[]

  What each cited page is, in sources order, on the SourceKind hierarchy. A host not in the source map is other, never guessed.

• data[].provenance.bestSourceKindSourceKind | null

  The strongest kind among the citations, or null when nothing is cited. manufacturer or standards_body means a figure can be checked against an authority; retailer or community alone means the record is still supported by copies of copies.

• data[].provenance.makerSourcestring | null

  The first cited page on the record's own manufacturer's website, or null when it cites none. A page on another maker's site does not count. Cited from the maker is not the same as checked against it: verifiedFields names the figures that were read against a source.

• data[].provenance.evidencestring

  How far the record's figures are backed, strongest first, for a badge: verified when at least one figure was read against a source (verifiedFields), maker when it cites a page on its own manufacturer's site (makerSource), authority when it cites a maker, standards body or government page, secondary when it cites only press, retailers, references or forums, none when it cites nothing. Derived from the fields beside it.

• data[].provenance.checksobject

  The checks the record has been through, on a single record's response only: every task the data agent (Redback) or a person was given about it, what each proposed, the pages it read, and whether a person accepted it. Nothing an agent proposes reaches the record until a person accepts it, so this is the trail behind verifiedFields. Who reviewed is not published; an agent's instance name is.

• data[].provenance.dataConfidencenumber | null

  The 0 to 1 score set from what was actually sourced, never raised by hand. See the confidence bands in the docs.

• data[].provenance.verifiedAtstring | null

  When a source was last read against this record. Null means the row is still seed knowledge.

• data[].provenance.verifiedFieldsstring[]

  Which fields the source stated, as an array. Everything else on a verified row is still unverified. Null where no source has been read.

• data[].provenance.specSourcestring | null

  Cartridges only: the page the drawing figures were taken from. Null on every other kind of record.

• data[].provenance.updatedAtstring

  When a served column last changed; the same value the record carries at the top level.

• data[].provenance.versionstring | null

  The record's content version, equal to the top-level version; equal versions mean equal data.

• data[].versionstring | null

  Opaque fingerprint of this record. It changes when and only when a field we serve changes, so a client holding the same value already has the record and need not fetch it. Equality is the only supported operation: do not parse it, and do not assume how it is computed. Null means the record has not been written since versioning began, not that it is unchanged.

• pagination.pagenumber

  Current page number

• pagination.per_pagenumber

  Items per page

• pagination.totalnumber

  Total matching records (Builder and above)

• 400VALIDATION_ERRORValidation error
• 401UNAUTHORIZEDAPI key required
• 403FORBIDDENValid key, not permitted
• 429RATE_LIMITEDRate limit exceeded
• 500INTERNAL_ERRORUnexpected server error

• X-API-Keystringheaderrequired

  Your API key. Authorization: Bearer <key> is accepted in its place.

• idstringrequired

  Ammunition load slug

  Accepts

  a lowercase slug: letters, digits and hyphens

  Example

  m882

• dataAmmunitionLoad

  A specific factory ammunition load within a caliber.

• data.idstring

  URL-safe slug identifying the load, e.g. 9mm-124gr-fmj.

• data.caliberIdstring

  Slug of the cartridge. Resolve against /v1/calibers/{id}.

• data.namestring

  Display name, as the maker writes it.

• data.designationstring | null

  Military or standards designation for the load, e.g. M882.

• data.manufacturerstring | null

  Who makes it.

• data.countryOfOriginstring | null

  ISO 3166-1 alpha-2 code of where it was designed, e.g. AT.

• data.bulletWeightGnumber

  Bullet weight in grams. Divide by 0.0648 for grains.

• data.bulletTypestring

  Bullet construction: fmj, jhp, sp, match.

• data.ballisticCoefficientG1number | null

  Ballistic coefficient against the G1 drag model, the convention for flat-based bullets.

• data.ballisticCoefficientG7number | null

  Ballistic coefficient against the G7 drag model, which fits boat-tail rifle bullets better than G1.

• data.referenceVelocityMpsnumber

  Muzzle velocity in metres per second at the reference barrel length below, not at the barrel of any particular firearm.

• data.referenceBarrelLengthMmnumber

  Barrel length in millimetres the reference velocity was measured from. Velocity for another barrel is extrapolated from this pair.

• data.sectionalDensitynumber | null

  Bullet mass divided by the square of its diameter. Higher penetrates better, all else equal.

• data.yearIntroducedinteger | null

  Year it entered production or service. Null where the date is disputed or unknown.

• data.isCommoninteger

  1 when the load is commonly stocked.

• data.bulletSvgUrlstring | null

  Absolute URL of the rendered bullet diagram.

• data.velocityRetentionExponentnumber | null

  Decay exponent used when extrapolating velocity to a barrel length other than the reference one.

• data.descriptionstring | null

  Prose summary of the record, where one has been written.

• data.isMilitaryinteger

  1 when the load is a military issue round.

• data.createdAtstring

  When the record was first added, YYYY-MM-DD HH:MM:SS in UTC.

• data.updatedAtstring

  When a field we serve last changed. Maintained by the database rather than by whatever wrote the row, so it moves for a corrected figure and does not move for a re-run of the seed. Before migration 0113 the seed rewrote every load on every run, and this said so.

• data.sourcesstring[]

  Where the figures came from. Null on every load today: this family has somewhere to cite from and nothing cited yet, which the data quality page counts as a gap rather than hiding. Check a velocity against the maker until it is filled.

• data.dataConfidencenumber | null

  How well specified the load is, on the same 0 to 1 scale as a firearm's. Null until there are sources behind it: a confidence figure with nothing supporting it looks like evidence and is not.

• data.provenanceProvenance

  Where a record's figures came from and how far they have been checked, in one place. sources are the pages consulted; check a specific figure against those. sourceKinds says what each page is and bestSourceKind the strongest of them, on the hierarchy SourceKind defines: a maker or standards-body page is evidence for a figure, a retailer or forum page is evidence the item exists. dataConfidence is the 0 to 1 score set from what was actually sourced and never raised by hand. verifiedAt and verifiedFields say when a source was last read against the record and which fields it stated; null means the row is still seed knowledge. updatedAt and version are the same cache signals the record carries at the top level.

• data.provenance.sourcesstring[]

  The pages consulted when the record was compiled, as an array. Check a specific figure against these rather than against dataConfidence.

• data.provenance.sourceKindsobject[]

  What each cited page is, in sources order, on the SourceKind hierarchy. A host not in the source map is other, never guessed.

• data.provenance.bestSourceKindSourceKind | null

  The strongest kind among the citations, or null when nothing is cited. manufacturer or standards_body means a figure can be checked against an authority; retailer or community alone means the record is still supported by copies of copies.

• data.provenance.makerSourcestring | null

  The first cited page on the record's own manufacturer's website, or null when it cites none. A page on another maker's site does not count. Cited from the maker is not the same as checked against it: verifiedFields names the figures that were read against a source.

• data.provenance.evidencestring

  How far the record's figures are backed, strongest first, for a badge: verified when at least one figure was read against a source (verifiedFields), maker when it cites a page on its own manufacturer's site (makerSource), authority when it cites a maker, standards body or government page, secondary when it cites only press, retailers, references or forums, none when it cites nothing. Derived from the fields beside it.

• data.provenance.checksobject

  The checks the record has been through, on a single record's response only: every task the data agent (Redback) or a person was given about it, what each proposed, the pages it read, and whether a person accepted it. Nothing an agent proposes reaches the record until a person accepts it, so this is the trail behind verifiedFields. Who reviewed is not published; an agent's instance name is.

• data.provenance.dataConfidencenumber | null

  The 0 to 1 score set from what was actually sourced, never raised by hand. See the confidence bands in the docs.

• data.provenance.verifiedAtstring | null

  When a source was last read against this record. Null means the row is still seed knowledge.

• data.provenance.verifiedFieldsstring[]

  Which fields the source stated, as an array. Everything else on a verified row is still unverified. Null where no source has been read.

• data.provenance.specSourcestring | null

  Cartridges only: the page the drawing figures were taken from. Null on every other kind of record.

• data.provenance.updatedAtstring

  When a served column last changed; the same value the record carries at the top level.

• data.provenance.versionstring | null

  The record's content version, equal to the top-level version; equal versions mean equal data.

• data.versionstring | null

  Opaque fingerprint of this record. It changes when and only when a field we serve changes, so a client holding the same value already has the record and need not fetch it. Equality is the only supported operation: do not parse it, and do not assume how it is computed. Null means the record has not been written since versioning began, not that it is unchanged.

• 400VALIDATION_ERRORValidation error
• 401UNAUTHORIZEDAPI key required
• 403FORBIDDENValid key, not permitted
• 404NOT_FOUNDResource not found
• 429RATE_LIMITEDRate limit exceeded
• 500INTERNAL_ERRORUnexpected server error

• X-API-Keystringheaderrequired

  Your API key. Authorization: Bearer <key> is accepted in its place.

• idstringrequired

  Ammunition load slug

  Accepts

  a lowercase slug: letters, digits and hyphens

  Example

  m882

• barrel_length_mmnumber

  Barrel length to adjust muzzle velocity for

  Range

  50 – 2000

  Example

  114

• distancesstring

  Comma-separated distances in metres

  Example

  0,100,200,300,500

• zero_minteger

  Zero distance in metres, where the bullet crosses the line of sight. Defaults to 25 for a handgun and 100 for a long gun.

  Range

  10 – 1000

  Example

  25

• sight_height_mmnumber

  Line of sight above the bore, in mm. Defaults to 20 for a handgun and 38 for a long gun.

  Range

  0 – 150

  Example

  20

• dataobject

  The response payload.

• data.ammunitionobject

  The load the figures are for.

• data.ammunition.idstring

  Slug of the load the table was computed for.

• data.ammunition.namestring

  Display name, as the maker writes it.

• data.ammunition.caliberIdstring

  Slug of the cartridge. Resolve against /v1/calibers/{id}.

• data.barrelLengthMmnumber | null

  Barrel length in millimetres, measured from the breech face.

• data.muzzleVelocityMpsnumber

  Muzzle velocity in metres per second, for the default load.

• data.muzzleEnergyJnumber

  Muzzle energy in joules, for the default load.

• data.effectiveRangeMnumber

  Effective range in metres against a point target.

• data.terminalBallisticsTerminalBallistics

  Terminal performance indices computed at the muzzle.

• data.terminalBallistics.tkoFactornumber

  Taylor Knock-Out factor.

• data.terminalBallistics.momentumKgMsnumber

  Momentum in kilogram-metres per second.

• data.terminalBallistics.sectionalDensitynumber

  Bullet mass divided by the square of its diameter. Higher penetrates better, all else equal.

• data.terminalBallistics.hatcherRSPnumber

  Hatcher Relative Stopping Power.

• data.terminalBallistics.energyDensityJCm2number

  Energy per unit frontal area, in joules per square centimetre.

• data.zeroingZeroing

  How the gun is assumed sighted for pathCm. Neither figure is recorded per gun, so each is an assumption the caller may override with zero_m and sight_height_mm: a handgun zeroed at 25 m with its sights 20 mm above the bore, a long gun at 100 m with an optic 38 mm above it.

• data.zeroing.zeroMnumber

  The distance at which the bullet crosses the line of sight, in m.

• data.zeroing.sightHeightMmnumber

  The line of sight above the bore, in mm.

• data.trajectoryTrajectoryPoint[]

  The solution sampled at each requested distance.

• data.trajectory[].distanceMnumber

  Distance from the muzzle in metres.

• data.trajectory[].velocityMpsnumber

  Remaining velocity at this distance, in metres per second.

• data.trajectory[].energyJnumber

  Remaining energy at this distance, in joules.

• data.trajectory[].dropCmnumber

  Drop below the bore line at this distance, in cm: the fall under gravity alone, with no sighting.

• data.trajectory[].pathCmnumber

  Height relative to the line of sight at this distance, in cm, negative below: how a drop table reads, for the answer's zeroing (the gun zeroed at zeroM with its sights sightHeightMm above the bore). Starts at minus the sight height at the muzzle and is 0 at the zero.

• data.trajectory[].timeOfFlightSnumber

  Time of flight to this distance, in seconds.

• data.trajectory[].machNumbernumber

  Velocity as a multiple of the speed of sound. Below ~1.2 the projectile is transonic and destabilises.

• data.trajectory[].momentumKgMsnumber

  Momentum in kilogram-metres per second.

• data.trajectory[].tkoFactornumber

  Taylor Knock-Out factor at this distance.

• data.trajectory[].energyDensityJCm2number

  Energy per unit frontal area, in joules per square centimetre.

• 400VALIDATION_ERRORValidation error
• 401UNAUTHORIZEDAPI key required
• 403FORBIDDENValid key, not permitted
• 404NOT_FOUNDResource not found
• 429RATE_LIMITEDRate limit exceeded
• 500INTERNAL_ERRORUnexpected server error

• X-API-Keystringheader

  Optional. Without a key this endpoint answers under the public policy; a key raises your limits and unlocks plan-gated fields. Authorization: Bearer <key> is accepted in its place.

• idstringrequired

  Ammunition load slug

  Accepts

  a lowercase slug: letters, digits and hyphens

  Example

  m882

• Content-Typeheader

  image/svg+xml

• Cache-Controlheader

  public, max-age=86400, s-maxage=604800 (cached for 24h client / 7 days CDN)

• 400VALIDATION_ERRORValidation error
• 404NOT_FOUNDResource not found
• 429RATE_LIMITEDRate limit exceeded
• 500INTERNAL_ERRORUnexpected server error