Load Firearm
Returns the full ballistic profile for a firearm chambered with a given load: muzzle velocity and energy, effective range, terminal indices, and the trajectory sampled from the muzzle out to 1000 m.
- stringheaderrequired
Your API key.
Authorization: Bearer <key>is accepted in its place.
- stringrequired
Resource slug ID
- Accepts
- a lowercase slug: letters, digits and hyphens
- Example
- string
Ammunition load to chamber. Defaults to the firearm default load, then the first common load for its primary caliber.
- Max length
- 255
- Example
- object
The response payload.
- BallisticsFirearm
The firearm the solution was computed for.
barrelLengthMmis absent when the firearm has no recorded barrel. - string
URL-safe slug identifying the firearm, e.g.
glock-17-gen5. - string
Display name, as the maker writes it.
- number
Barrel length in millimetres, measured from the breech face.
- object
The load the calculation used.
- string
Slug of the ammunition load the firearm was chambered with.
- string
Display name, as the maker writes it.
- string
Slug of the cartridge. Resolve against
/v1/calibers/{id}. - number
Bullet weight in grams. Divide by 0.0648 for grains.
- string
Bullet construction:
fmj,jhp,sp,match. - object
The figures derived for the barrel length asked about, rather than the reference one.
- number
Muzzle velocity in metres per second, for the default load.
- number
Muzzle energy in joules, for the default load.
- number
Effective range in metres against a point target.
- TerminalBallistics
Terminal performance indices computed at the muzzle.
- object
The figures published for this firearm, where the catalog records them.
- number | null
Muzzle velocity in metres per second, for the default load.
- number | null
Muzzle energy in joules, for the default load.
- number | null
Effective range in metres against a point target.
- TrajectoryPoint[]
The flight path, one row per distance step.
- number
Distance from the muzzle in metres.
- number
Remaining velocity at this distance, in metres per second.
- number
Remaining energy at this distance, in joules.
- number
Bullet drop below the line of sight at this distance, in centimetres.
- number
Time of flight to this distance, in seconds.
- number
Velocity as a multiple of the speed of sound. Below ~1.2 the projectile is transonic and destabilises.
- number
Momentum in kilogram-metres per second.
- number
Taylor Knock-Out factor at this distance.
- number
Energy per unit frontal area, in joules per square centimetre.
- string | null
Why the calculation could not be completed, or null when it succeeded.
- 400
VALIDATION_ERRORValidation error - 401
UNAUTHORIZEDAPI key required - 403
FORBIDDENValid key, not permitted - 404
NOT_FOUNDResource not found - 429
RATE_LIMITEDRate limit exceeded - 500
INTERNAL_ERRORUnexpected server error
Requires Builder tier or higher.
When ammo_id is omitted, the endpoint auto-resolves ammunition in this order: (1) the firearm's default ammunition, (2) the most common load for the caliber.
Muzzle velocity is adjusted based on the firearm's barrel length relative to the ammunition's reference barrel.
The trajectory table covers distances from 0 to the effective range at regular intervals.
Ideal for game engines that need a ready-to-use ballistic profile for a weapon.
- Minimum tier
- Builder+
- Monthly quota
- 25,000/mo
- Rate limit
- 60/min
- Daily cap
- 2,000
Figures shown are for this endpoint's minimum tier. Higher tiers raise every limit.