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10% Ordnance Gelatin (FBI Protocol)

Definition

Porcine or bovine gelatin at 10 g per 100 mL water, chilled to 4°C, calibrated with a 4.5mm steel BB at 590 fps. The BB must penetrate 8.3-9.5 cm. Used by FBI, most US law-enforcement agencies, and UK CAST as the standard terminal-performance test medium.

Concentration
10 g gelatin per 100 mL water
Test temperature
Chilled to 4°C before firing
Calibration shot
4.5 mm steel BB at 590 fps
Acceptable BB penetration
8.3-9.5 cm
Adopted by
FBI, most US LE agencies, UK CAST

Common questions

Why is the gelatin calibrated with a BB shot before it is used for testing?+

Gelatin batches vary with temperature, humidity and age, so firing a standard 4.5 mm steel BB and checking it penetrates 8.3-9.5 cm confirms the block's density and elasticity are within the accepted range before any ammunition test data from it is trusted.

How does 10% gelatin differ from the 20% NATO protocol?+

It uses half the gelatin concentration and a warmer 4°C conditioning temperature, giving a softer block intended to model soft tissue penetration, whereas the 20% NATO block is denser and meant to approximate a broader range of body tissue.

Does passing an FBI gelatin test guarantee real-world wound performance?+

No. Ordnance gelatin is a standardized surrogate used to compare ammunition consistently, not a literal replica of bone, clothing layers or individual physiology, so results are comparative rather than predictive of an actual wound.

Related terms

20% Ordnance Gelatin (NATO Protocol)
Gelatin at 20 g per 100 mL water, at 10°C. Higher concentration produces greater penetration resistance, modelling the full human body including...
Back-Face Deformation (BFD)
The indentation left in Roma Plastilina No. 1 clay backing material behind an armour panel after a bullet impact that does not...
Clear Ballistics (Permagel)
A synthetic polymer-based ballistic test medium formulated to match 10% ordnance gelatin at 4°C. Optically clear (allows high-speed video of bullet penetration),...
IS 17051-2018
The Bureau of Indian Standards specification for personal body armour, published 2018. Defines four protection levels tested against 9mm FMJ, 7.62x25mm Tokarev...
NIJ Standard 0101.06
The National Institute of Justice (US DOJ) body armour performance standard, published 2008. Defines five protection levels (IIA, II, IIIA, III, IV)...

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