Data Methodology

This page explains where our data comes from, how sourcing decisions are made when sources conflict, how calculated fields differ from measured values, and what the limitations of this data are for safety-critical decisions like reloading.

• 1Data source hierarchy
• 2Calculated vs. measured fields
• 3Pressure standards and why they differ
• 4Powder equivalences — what they mean and what they don't
• 5Corrections and disputes
• 6Safety disclaimer

1. Data Source Hierarchy

When sources conflict, we follow a defined hierarchy. Higher-numbered sources are used only when no higher-priority source covers the value in question.

Cartridge specifications

1. SAAMI — Sporting Arms and Ammunition Manufacturers' Institute. Primary source for all US commercial cartridges.
2. CIP — Commission Internationale Permanente pour l'épreuve des armes à feu portatives. Primary source for European cartridges and the basis for NATO standardization.
3. NATO STANAG — NATO Standardization Agreement documentation. Used for military cartridges where SAAMI/CIP coverage is incomplete.
4. Manufacturer technical specifications — Official published data from the cartridge or firearm manufacturer.
5. Historical reference texts — Used for obsolete and wildcat cartridges not standardized by any of the above bodies. Source cited on the record.
6. Secondary references — Used only when no primary source is available. Noted in the record as secondary-sourced.

Powder data

1. Manufacturer published data sheets — Primary source. Covers burn rate position, grain shape, relative burn rate, and application guidance.
2. Official published reloading manuals — Hodgdon, Lyman, Sierra, Hornady, Nosler, and others. Primary source for charge weight data.
3. Manufacturer burn-rate comparison charts — Published relative rankings used to cross-reference position in the overall burn rate spectrum.
4. ADI/Hodgdon published equivalence tables — Used specifically for confirmed ADI equivalences (e.g., AR2206H / H4831).

Burn-rate positions that cannot be confirmed from a primary source are marked as estimated on the powder record.

Factory load data

1. Manufacturer product data — Advertised muzzle velocity, bullet weight, bullet type, BC where published. This is what's shown as the primary specification.
2. Retailer catalog data — Used to fill gaps in manufacturer data and to track SKU/UPC assignments.
3. Calculated fields — Muzzle energy, trajectory data, and recoil index are computed from the above. These are labeled calculated, not measured. See Section 2.

Competition data

Sourced from USPSA, IDPA, ATA, NSCA, and SASS match databases. Records are scraped and verified on a rolling basis. Competition schedules change without notice. Always verify current status with the organizing club before traveling to a match.

Range and location data

Sourced from ATF FFL records (for licensed dealers) and public records (for ranges and clubs). User-submitted corrections are reviewed before being applied. Business hours, services, and contact information change — verify directly with the facility.

2. Calculated vs. Measured Fields

Several fields displayed on this site are computed from published specifications, not taken from direct measurement. These are clearly labeled in the interface. The following table defines how each is computed and what its limitations are.

Field	Type	Method / Notes
Muzzle velocity	Sourced	Manufacturer-advertised figure. Test barrel length varies by manufacturer and is not always disclosed.
Muzzle energy	Calculated	Computed from advertised velocity and bullet weight using KE = ½mv². Reflects the published velocity figure — not an independently measured muzzle energy.
Ballistic coefficient (BC)	Sourced	Manufacturer-published G1 or G7 value where available. When not published, the field is blank — we do not estimate BC.
Trajectory / drop	Calculated	G1 point-mass numerical integration. Standard atmosphere assumed (59°F, sea level, 29.92 inHg). Sight height 1.5" above bore. Zero distance as selected. Results are reference estimates — not precision firing solutions. Real-world results vary by barrel length, altitude, temperature, and ammunition lot.
Recoil index	Calculated	Normalized momentum score derived from bullet weight, velocity, and powder charge where available. Does not account for firearm weight, gas system, muzzle device, stock fit, or grip. Two loads with the same recoil index will not feel identical in different firearms.
Burn-rate position	Sourced	From manufacturer published data where available. Marked as estimated when derived from third-party comparison charts rather than a primary source.

3. Pressure Standards and Why They Differ

SAAMI and CIP use different measurement methods and different acceptance criteria. This means a cartridge can carry two different pressure values — both technically correct — simply because they were measured by different conventions.

SAAMI specifications for most modern cartridges use piezoelectric transducer measurements. Older SAAMI and CIP specifications were derived using copper crusher gauges. The two measurement methods do not produce numerically equivalent results even when measuring the same chamber event. SAAMI's current conversion factor for comparing the two is documented but does not account for all cartridge geometries equally.

Additionally, CIP specifies maximum average pressure (MAP) while SAAMI specifies maximum average pressure using a different statistical basis. The CIP acceptance criterion also includes a separate limit on the highest individual pressure reading, which SAAMI does not express the same way.

In practice: a cartridge can be fully within SAAMI specification and fully within CIP specification at different stated pressure values. Neither number is wrong.

Where both SAAMI and CIP values exist for a cartridge, both are shown on the cartridge page with the standard labeled. We do not reduce two valid values to one.

4. Powder Equivalences — What They Mean and What They Don't

Powder equivalences listed on this site are sourced from manufacturer-published tables or confirmed ADI/Hodgdon equivalence documentation. An equivalence relationship means the two powders occupy a similar burn-rate position and have comparable application ranges.

When substituting powders, always use charge data published specifically for that powder, in that cartridge, from a current published reloading manual. Start at the minimum charge listed and work up using standard pressure-sign observation procedure. Do not interpolate between manuals or assume equivalent powders share identical charge ranges.

The powder substitution data on this site is provided for reference identification purposes — to help you identify what powders to look up in a reloading manual, not to provide the charge data itself.

5. Corrections and Disputes

Data corrections can be submitted at lindcottarmory.com/suggest. When a correction is received:

1. The submitted value is compared against the primary source for that data type (following the hierarchy in Section 1).
2. If the primary source confirms the correction, the record is updated and the source note is updated to reflect the verification.
3. If the primary source does not confirm the correction, we note that it was reviewed and declined, and why.

For disputed values — cases where SAAMI, CIP, and manufacturer specifications all give different numbers for the same field — we note the conflict in the record rather than silently choosing one. The goal is to accurately represent the state of the data, including its ambiguities, not to paper over disagreements between authoritative sources.

If you believe a record is materially wrong, particularly for pressure specifications or powder charge data, please submit a correction with the specific source you're citing. We take pressure-related corrections seriously.

6. Safety Disclaimer

Ballistic trajectory data, muzzle energy values, and recoil estimates are computational outputs based on manufacturer-published inputs. They are reference estimates, not precision measurements. Do not use trajectory calculations as a substitute for confirmed dope from actual firing. Actual results vary by barrel length, ammunition lot, atmospheric conditions, and firearm condition.

Pressure specifications are sourced from SAAMI and CIP documentation as described above. They describe the standard for commercially produced ammunition and are not load development data. Do not use published maximum case pressure as a reloading target.

Competition schedule data may lag actual scheduling. Always verify match status directly with the organizing club before traveling.

Range and dealer data is sourced from public records and may be out of date. Verify hours, services, and accessibility directly with the facility.

Lindcott Armory LLC provides this data as a reference resource. It is not professional instruction, legal advice, or safety certification. Use it accordingly.

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Questions about specific data sources or methodology decisions: support@lindcottarmory.com

Data corrections: lindcottarmory.com/suggest