gunspec-io · Schema
AmmunitionLoad
A specific factory ammunition load within a caliber.
FirearmsAPIDatabaseSpecificationsSDKMCP
Properties
| Name | Type | Description |
|---|---|---|
| id | string | URL-safe slug identifying the load, e.g. `9mm-124gr-fmj`. |
| caliberId | string | Slug of the cartridge. Resolve against `/v1/calibers/{id}`. |
| name | string | Display name, as the maker writes it. |
| designation | stringnull | Military or standards designation for the load, e.g. `M882`. |
| manufacturer | stringnull | Who makes it. |
| countryOfOrigin | stringnull | ISO 3166-1 alpha-2 code of where it was designed, e.g. `AT`. |
| bulletWeightG | number | Bullet weight in grams. Divide by 0.0648 for grains. |
| bulletType | string | Bullet construction: `fmj`, `jhp`, `sp`, `match`. |
| ballisticCoefficientG1 | numbernull | Ballistic coefficient against the G1 drag model, the convention for flat-based bullets. |
| ballisticCoefficientG7 | numbernull | Ballistic coefficient against the G7 drag model, which fits boat-tail rifle bullets better than G1. |
| referenceVelocityMps | number | Muzzle velocity in metres per second **at the reference barrel length below**, not at the barrel of any particular firearm. |
| referenceBarrelLengthMm | number | Barrel length in millimetres the reference velocity was measured from. Velocity for another barrel is extrapolated from this pair. |
| sectionalDensity | numbernull | Bullet mass divided by the square of its diameter. Higher penetrates better, all else equal. |
| yearIntroduced | integernull | Year it entered production or service. Null where the date is disputed or unknown. |
| isCommon | integer | 1 when the load is commonly stocked. |
| bulletSvgUrl | stringnull | Absolute URL of the rendered bullet diagram. |
| velocityRetentionExponent | numbernull | Decay exponent used when extrapolating velocity to a barrel length other than the reference one. |
| description | stringnull | Prose summary of the record, where one has been written. |
| isMilitary | integer | 1 when the load is a military issue round. |
| createdAt | string | When the record was first added, `YYYY-MM-DD HH:MM:SS` in UTC. |
| updatedAt | string | 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 01 |
| sources | arraynull | 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 ag |
| dataConfidence | numbernull | 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. |
| provenance | object | |
| version | stringnull | 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 support |
JSON Schema
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"$id": "https://artifacts.apis.io/gunspec-io/json-schema/gunspec-io-ammunition-load-schema.json",
"title": "AmmunitionLoad",
"description": "A specific factory ammunition load within a caliber.",
"x-generated": "2026-10-30",
"x-method": "derived",
"x-generator": "derive-json-schema.py",
"x-source": "openapi/gunspec-io-openapi.json#/components/schemas/AmmunitionLoad",
"type": "object",
"properties": {
"id": {
"type": "string",
"description": "URL-safe slug identifying the load, e.g. `9mm-124gr-fmj`."
},
"caliberId": {
"type": "string",
"description": "Slug of the cartridge. Resolve against `/v1/calibers/{id}`."
},
"name": {
"type": "string",
"description": "Display name, as the maker writes it."
},
"designation": {
"type": [
"string",
"null"
],
"description": "Military or standards designation for the load, e.g. `M882`."
},
"manufacturer": {
"type": [
"string",
"null"
],
"description": "Who makes it."
},
"countryOfOrigin": {
"type": [
"string",
"null"
],
"description": "ISO 3166-1 alpha-2 code of where it was designed, e.g. `AT`."
},
"bulletWeightG": {
"type": "number",
"description": "Bullet weight in grams. Divide by 0.0648 for grains."
},
"bulletType": {
"type": "string",
"description": "Bullet construction: `fmj`, `jhp`, `sp`, `match`."
},
"ballisticCoefficientG1": {
"type": [
"number",
"null"
],
"description": "Ballistic coefficient against the G1 drag model, the convention for flat-based bullets."
},
"ballisticCoefficientG7": {
"type": [
"number",
"null"
],
"description": "Ballistic coefficient against the G7 drag model, which fits boat-tail rifle bullets better than G1."
},
"referenceVelocityMps": {
"type": "number",
"description": "Muzzle velocity in metres per second **at the reference barrel length below**, not at the barrel of any particular firearm."
},
"referenceBarrelLengthMm": {
"type": "number",
"description": "Barrel length in millimetres the reference velocity was measured from. Velocity for another barrel is extrapolated from this pair."
},
"sectionalDensity": {
"type": [
"number",
"null"
],
"description": "Bullet mass divided by the square of its diameter. Higher penetrates better, all else equal."
},
"yearIntroduced": {
"type": [
"integer",
"null"
],
"description": "Year it entered production or service. Null where the date is disputed or unknown."
},
"isCommon": {
"type": "integer",
"description": "1 when the load is commonly stocked."
},
"bulletSvgUrl": {
"type": [
"string",
"null"
],
"description": "Absolute URL of the rendered bullet diagram."
},
"velocityRetentionExponent": {
"type": [
"number",
"null"
],
"description": "Decay exponent used when extrapolating velocity to a barrel length other than the reference one."
},
"description": {
"type": [
"string",
"null"
],
"description": "Prose summary of the record, where one has been written."
},
"isMilitary": {
"type": "integer",
"description": "1 when the load is a military issue round."
},
"createdAt": {
"type": "string",
"description": "When the record was first added, `YYYY-MM-DD HH:MM:SS` in UTC."
},
"updatedAt": {
"type": "string",
"description": "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."
},
"sources": {
"type": [
"array",
"null"
],
"items": {
"type": "string"
},
"description": "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."
},
"dataConfidence": {
"type": [
"number",
"null"
],
"description": "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."
},
"provenance": {
"$ref": "#/$defs/Provenance"
},
"version": {
"type": [
"string",
"null"
],
"description": "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."
}
},
"required": [
"id",
"caliberId",
"name",
"bulletWeightG",
"bulletType",
"referenceVelocityMps"
],
"$defs": {
"Provenance": {
"type": "object",
"description": "Where a record's figures came from and how far they have been checked, in one place. `sources` are the pages consulted; check a specific figure against those. `sourceKinds` says what each page is and `bestSourceKind` the strongest of them, on the hierarchy `SourceKind` defines: a maker or standards-body page is evidence for a figure, a retailer or forum page is evidence the item exists. `dataConfidence` is the 0 to 1 score set from what was actually sourced and never raised by hand. `verifiedAt` and `verifiedFields` say when a source was last read against the record and which fields it stated; null means the row is still seed knowledge. `updatedAt` and `version` are the same cache signals the record carries at the top level.",
"properties": {
"sources": {
"type": "array",
"items": {
"type": "string"
},
"description": "The pages consulted when the record was compiled, as an array. Check a specific figure against these rather than against `dataConfidence`."
},
"sourceKinds": {
"type": "array",
"items": {
"type": "object",
"properties": {
"url": {
"type": "string",
"description": "Absolute, directly fetchable URL."
},
"kind": {
"$ref": "#/$defs/SourceKind"
},
"archivedFrom": {
"type": [
"string",
"null"
],
"description": "The original address when `url` is a Wayback Machine capture of it. A cited page that no longer answers is replaced by its last capture that answered 200, so the citation still shows what its author read; `kind` is the original page's."
},
"rank": {
"type": "integer",
"description": "The kind's place in the source hierarchy: 0 is the maker, the strongest; higher is weaker."
},
"tier": {
"type": "string",
"enum": [
"authority",
"classified",
"unclassified"
],
"description": "Where the site stands in the source registry (`/v1/data/sources`): an authority (the maker, a standards body, a government), a classified site, or one not yet classed."
},
"basis": {
"type": "string",
"enum": [
"declared",
"maker",
"rule",
"unclassified"
],
"description": "What the class rests on: classed by a person, a catalogued maker's own site, a .gov or .mil domain, or nothing yet."
},
"evidence": {
"type": [
"string",
"null"
],
"description": "The words the site was classed on, where a person recorded them."
}
},
"required": [
"url",
"kind",
"archivedFrom",
"rank",
"tier",
"basis",
"evidence"
]
},
"description": "What each cited page is, in `sources` order, on the `SourceKind` hierarchy. A host not in the source map is `other`, never guessed."
},
"bestSourceKind": {
"anyOf": [
{
"$ref": "#/$defs/SourceKind"
},
{
"type": "null"
}
],
"description": "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."
},
"makerSource": {
"type": [
"string",
"null"
],
"description": "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."
},
"evidence": {
"type": "string",
"enum": [
"verified",
"maker",
"authority",
"secondary",
"none"
],
"description": "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."
},
"checks": {
"type": "object",
"description": "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.",
"properties": {
"raised": {
"type": "integer",
"description": "Every task ever raised on the record, answered or not."
},
"open": {
"type": "integer",
"description": "Tasks still waiting to be worked."
},
"history": {
"type": "array",
"description": "The latest twenty, newest first.",
"items": {
"type": "object",
"properties": {
"task": {
"type": "string",
"description": "The task id, stable across runs; the same id `/v1/data/tasks/{taskKey}` answers for."
},
"number": {
"type": [
"integer",
"null"
],
"description": "The task's number; `/v1/data/tasks/{number}` loads it as its key does."
},
"check": {
"type": [
"string",
"null"
],
"description": "The check that raised it, where one did."
},
"kind": {
"type": "string",
"description": "`verify` reads the record against its maker's page, `gap` researches an empty field, `contradiction` judges fields that disagree, `vocabulary` a value outside a list."
},
"agent": {
"type": [
"string",
"null"
],
"description": "`redback` when the agent worked it, `staff` when a person did, null when nobody has."
},
"worker": {
"type": [
"string",
"null"
],
"description": "The agent instance that worked it; null for a person."
},
"status": {
"type": "string",
"description": "`resolved` (a proposal was filed), `unverifiable` (nothing could be established; retried after a cooldown), `not_a_fault`, or open."
},
"decidedAt": {
"type": [
"string",
"null"
],
"description": "When the task was answered; null while it is open."
},
"proposed": {
"type": [
"string",
"null"
],
"description": "What it proposed, in its own words; null while it is open."
},
"fields": {
"type": "array",
"items": {
"type": "string"
},
"description": "Per-field completeness, keyed by column name."
},
"sources": {
"type": "array",
"items": {
"type": "string"
},
"description": "The pages it read and quoted."
},
"review": {
"type": [
"object",
"null"
],
"properties": {
"decision": {
"type": "string",
"enum": [
"accepted",
"rejected"
],
"description": "Whether a person accepted the proposal."
},
"at": {
"type": [
"string",
"null"
],
"description": "When they decided."
}
},
"description": "A person's decision on the proposal; null until reviewed."
},
"finding": {
"type": [
"object",
"null"
],
"description": "What the check found, where a check raised the task: its own line for this record and the figures it measured, so a reader sees how the value breaks the method. The same the public task board serves with `include=research`.",
"properties": {
"why": {
"type": [
"string",
"null"
],
"description": "The check's line for this record."
},
"evidence": {
"type": [
"object",
"null"
],
"additionalProperties": true,
"description": "The figures the check measured."
}
},
"required": [
"why",
"evidence"
]
}
},
"required": [
"task",
"number",
"check",
"kind",
"agent",
"worker",
"status",
"decidedAt",
"proposed",
"fields",
"sources",
"review",
"finding"
]
}
}
},
"required": [
"raised",
"open",
"history"
]
},
"dataConfidence": {
"type": [
"number",
"null"
],
"description": "The 0 to 1 score set from what was actually sourced, never raised by hand. See the confidence bands in the docs."
},
"verifiedAt": {
"type": [
"string",
"null"
],
"description": "When a source was last read against this record. Null means the row is still seed knowledge."
},
"verifiedFields": {
"type": [
"array",
"null"
],
"items": {
"type": "string"
},
"description": "Which fields the source stated, as an array. Everything else on a verified row is still unverified. Null where no source has been read."
},
"specSource": {
"type": [
"string",
"null"
],
"description": "Cartridges only: the page the drawing figures were taken from. Null on every other kind of record."
},
"updatedAt": {
"type": "string",
"description": "When a served column last changed; the same value the record carries at the top level."
},
"version": {
"type": [
"string",
"null"
],
"description": "The record's content version, equal to the top-level `version`; equal versions mean equal data."
}
},
"required": [
"sources",
"sourceKinds",
"bestSourceKind",
"makerSource",
"evidence",
"dataConfidence",
"verifiedAt",
"verifiedFields",
"specSource",
"updatedAt",
"version"
]
},
"SourceKind": {
"type": "string",
"enum": [
"manufacturer",
"standards_body",
"government",
"peer_reviewed",
"reference",
"aggregator",
"press",
"retailer",
"community",
"other"
],
"description": "What kind of page a cited source is, strongest first: the maker's own page, a standards body (SAAMI, C.I.P.), a government or military document, an independent reference work, a specification aggregator, the press, a retailer or auction listing, a community site, or an unclassified page. Weigh a figure by the best kind behind it, never by how many pages were cited."
}
}
}Work with this as data
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