NATO EPVAT testing
Encyclopedia
NATO EPVAT testing is one of the three recognized classes of procedures used in the world to control the safety and quality of firearms ammunition
.
Beside this, there are also the Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives
(CIP) class of procedures and the Sporting Arms and Ammunition Manufacturers' Institute
(SAAMI) class of procedures.
EPVAT Testing is described in unclassified documents by NATO, more precisely by the AC/225 Army Armaments Group (NAAG).
EPVAT is an abbreviation for "Electronic Pressure Velocity and Action Time". This is a comprehensive procedure for testing ammunition using state-of-the-art instruments and computers. The procedure itself is described in NATO document AC/225 (Com. III/SC.1)D/200.
Unlike the C.I.P. procedures aiming only at the user's safety, the NATO procedures for ammunition testing also includes comprehensive functional quality testing in relation with the intended use. That is, not only the soldier's safety is looked at, but also his capacity to incapacitate the enemy. As a result, for every ammunition order by NATO, a complete acceptance approval on both safety and functionality is performed by both NATO and the relevant ammunition manufacturers in a contradictory fashion.
For this, a highly accurate and indisputable protocol has been defined by NATO experts using a system of reference cartridges.
The civilian organisations C.I.P. and SAAMI use less comprehensive test procedures than NATO, but NATO test centres have the advantage that only a few chamberings are in military use. The C.I.P. and SAAMI proof houses must be capable of testing hundreds of different chamberings requiring lots of different test barrels, etc..
This test is performed under normal conditions but also by simulating extreme polar
or desert
conditions using special cooling equipment and oven
s to cool or heat the tested ammunition to the appropriate temperatures.
Proofing
The minimum proof and performance requirements for small arms ammunition of NATO calibres are covered in STANAG
s as follows:
Each weapon and component considered vulnerable to the effects of a rapid change in pressure, for example barrels, breech blocks and bolts, will be tested by firing one dry round at a corrected minimum of 25% over pressure and one oiled round at a corrected minimum of 25% over pressure. 25% over pressure means 25% in excess of the Service Pressure (Pmax). The Service Pressure is defined as the mean pressure generated by the Service Cartridge at a temperature of 21°C. Such a high pressure proof is conducted with both the weapon and ammunition conditioned to an ambient temperature of 21°C.
Each weapon will be individually tested, from an ammunition lot that produces a minimum corrected mean chamber pressure in accordance with the table below:
The above proof round pressure requirements for the 9 mm and 12.7 mm rounds established by the British Ministry of Defence
are higher than the current (2008) C.I.P. proof round pressure requirement legislation for the civilian equivalent 9mm Parabellum (C.I.P. Pmax rating 235 MPA / (34,083 psi) and .50 Browning (C.I.P. Pmax rating 370 MPA / (53,663 psi) rounds. The 9x19mm NATO round can be regarded as overpressure ammunition
(inexhaustive list)
Ammunition
Ammunition is a generic term derived from the French language la munition which embraced all material used for war , but which in time came to refer specifically to gunpowder and artillery. The collective term for all types of ammunition is munitions...
.
Beside this, there are also the Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives
Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives
The Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives is an international organisation whose members are 14 states, mainly European....
(CIP) class of procedures and the Sporting Arms and Ammunition Manufacturers' Institute
Sporting Arms and Ammunition Manufacturers' Institute
The Sporting Arms and Ammunition Manufacturers' Institute is an association of American firearms and ammunition manufacturers...
(SAAMI) class of procedures.
EPVAT Testing is described in unclassified documents by NATO, more precisely by the AC/225 Army Armaments Group (NAAG).
EPVAT is an abbreviation for "Electronic Pressure Velocity and Action Time". This is a comprehensive procedure for testing ammunition using state-of-the-art instruments and computers. The procedure itself is described in NATO document AC/225 (Com. III/SC.1)D/200.
Unlike the C.I.P. procedures aiming only at the user's safety, the NATO procedures for ammunition testing also includes comprehensive functional quality testing in relation with the intended use. That is, not only the soldier's safety is looked at, but also his capacity to incapacitate the enemy. As a result, for every ammunition order by NATO, a complete acceptance approval on both safety and functionality is performed by both NATO and the relevant ammunition manufacturers in a contradictory fashion.
For this, a highly accurate and indisputable protocol has been defined by NATO experts using a system of reference cartridges.
The civilian organisations C.I.P. and SAAMI use less comprehensive test procedures than NATO, but NATO test centres have the advantage that only a few chamberings are in military use. The C.I.P. and SAAMI proof houses must be capable of testing hundreds of different chamberings requiring lots of different test barrels, etc..
NATO Reference cartridges system
In this system, the ammunition manufacturers, in close cooperation with NATO, have set aside a batch (also termed "lot") of ammunition they consider to be of very good quality and representative of ammunition that should be delivered to the armies in the next following years. This batch is maintained at approved NATO test centres and distributed to the manufacturers involved. When a new batch (lot) is delivered, a set of 20 reference cartridges are fired to see how they behave with the local equipment and with the current atmospheric conditions. Results are then compared to the reference values as maintained by the NATO and correctors (delta values) are computed. Then, the current batch (lot) of ammunition is fired and the correctors are applied on the measured value giving a result "comparable" to the reference itself.This test is performed under normal conditions but also by simulating extreme polar
Polar region
Earth's polar regions are the areas of the globe surrounding the poles also known as frigid zones. The North Pole and South Pole being the centers, these regions are dominated by the polar ice caps, resting respectively on the Arctic Ocean and the continent of Antarctica...
or desert
Desert
A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...
conditions using special cooling equipment and oven
Oven
An oven is a thermally insulated chamber used for the heating, baking or drying of a substance. It is most commonly used for cooking. Kilns, and furnaces are special-purpose ovens...
s to cool or heat the tested ammunition to the appropriate temperatures.
ProofingProof testA proof test is a test wherein a deliberately over-pressured round is fired from a firearm in order to verify that the firearm is not defective and will not explode on firing. The firearm is inspected after the test, and if it is found to be in sound condition, then it is marked with a proof mark...
The minimum proof and performance requirements for small arms ammunition of NATO calibres are covered in STANAGSTANAG
STANAG is the NATO abbreviation for Standardization Agreement, which sets up processes, procedures, terms, and conditions for common military or technical procedures or equipment between the member countries of the alliance. Each NATO state ratifies a STANAG and implements it within their own...
s as follows:
- 5.56 mm. STANAG 4172 and NATO Manual of Proof and Inspection AC/225 (LG/3-SG/1) D/8.
- 7.62 mm. STANAG 2310 and NATO Manual of Proof and Inspection AC/225 (LG/3-SG/1) D/9.
- 9 mm. STANAG 4090 and NATO Manual of Proof and Inspection AC/225 (P111-SP1) D/170(REV).
- 12.7 mm. STANAG 4383 and NATO Manual of Proof and Inspection AC/225 (LG/3-SG/1) D/11.
Each weapon and component considered vulnerable to the effects of a rapid change in pressure, for example barrels, breech blocks and bolts, will be tested by firing one dry round at a corrected minimum of 25% over pressure and one oiled round at a corrected minimum of 25% over pressure. 25% over pressure means 25% in excess of the Service Pressure (Pmax). The Service Pressure is defined as the mean pressure generated by the Service Cartridge at a temperature of 21°C. Such a high pressure proof is conducted with both the weapon and ammunition conditioned to an ambient temperature of 21°C.
Each weapon will be individually tested, from an ammunition lot that produces a minimum corrected mean chamber pressure in accordance with the table below:
| Calibre | Specific Weapon Detail | Service Pressure Pmax MPa / (psi) |
Proof Round Pressure Requirement MPa / (psi) |
Detailed Requirement for Proof Ammunition |
|---|---|---|---|---|
| 5.56 mm (5.56×45mm NATO) | Designed to chamber NATO ammunition | 430.0 / (62,366) | 537.5 / (77,958) | Pressure recorded in NATO design EPVAT Barrel with Kistler 6215 Transducer or by equipment to Commission Internationale Permanente pour l’épreuve des Armes á Feu Portatives (C.I.P.) requirements |
| 7.62 mm (7.62×51mm NATO 7.62×51mm NATO The 7.62×51mm NATO is a rifle cartridge developed in the 1950s as a standard for small arms among NATO countries... ) |
Designed to chamber NATO ammunition | 415.0 / (60,190) | 519.0 / (75,275) | Pressure recorded in NATO design EPVAT Barrel with Kistler 6215 Transducer or by equipment to C.I.P. requirements |
| 9 mm (9×19mm NATO) | Designed to chamber NATO ammunition | 252.0 / (36,550) | 315.0 / (45,687) | Pressure recorded in C.I.P. design barrel at mid case position |
| 12.7 mm (12.7×99mm NATO) | Designed to chamber NATO ammunition | 417.0 / (60,481) | 521.3 / (75,608) | Pressure recorded in NATO design EPVAT Barrel with Kistler 6215 Transducer or by equipment to C.I.P. requirements |
| All other small arms ammunition for use in "non-NATO Chamber" weapons | As defined by the current C.I.P. legislation. | As defined by the current C.I.P. legislation. |
The above proof round pressure requirements for the 9 mm and 12.7 mm rounds established by the British Ministry of Defence
Ministry of Defence (United Kingdom)
The Ministry of Defence is the United Kingdom government department responsible for implementation of government defence policy and is the headquarters of the British Armed Forces....
are higher than the current (2008) C.I.P. proof round pressure requirement legislation for the civilian equivalent 9mm Parabellum (C.I.P. Pmax rating 235 MPA / (34,083 psi) and .50 Browning (C.I.P. Pmax rating 370 MPA / (53,663 psi) rounds. The 9x19mm NATO round can be regarded as overpressure ammunition
Overpressure ammunition
Overpressure ammunition, commonly designated as +P or +P+, is small arms ammunition that has been loaded to a higher internal pressure than is standard for ammunition of its caliber , but less than the pressures generated by a proof round...
Testing equipment providers
The following companies provide equipment to the NATO armies to perform this type of testing:(inexhaustive list)
- Deby & Co, Ltd (Belgium)
- DRELLO GmbH (Germany)
- HPI (Austria)
- Kistler InternationalKistler-People:* Darci Kistler, American ballerina* Rives Kistler, American judge* Steven Kistler, American scientist, inventor of aerogels* Walter Kistler, Swiss physicist and inventor-Places:* Kistler, Pennsylvania, a borough in Mifflin County...
- MS Instruments (England)
- Prototypa (Czech Republic)
- Sabre (England)
- Stas (Italy)
See also
- FirearmFirearmA firearm is a weapon that launches one, or many, projectile at high velocity through confined burning of a propellant. This subsonic burning process is technically known as deflagration, as opposed to supersonic combustion known as a detonation. In older firearms, the propellant was typically...
s - AmmunitionAmmunitionAmmunition is a generic term derived from the French language la munition which embraced all material used for war , but which in time came to refer specifically to gunpowder and artillery. The collective term for all types of ammunition is munitions...
- NATO
- NATO cartridge
- C.I.P.
- SAAMISaamiSaami or SAAMI can stand for:*Sami people*Sami languages*Sporting Arms and Ammunition Manufacturers' Institute...
External links
- Army Armaments Group (NAAG)
- Thales brochure on 5.56mm F1 ball ammunition conforming to the design parameters of the NATO STANAG 4172 and tested with Kistler 6215 transducers at different temperatures
- THE ANALYSIS OF APPLICATION AND REQUIREMENTS SMALL CALIBER REFERENCE AMMUNITION AND POLISH ACHIEVEMENT IN THE FIELD OF WORKING OUT NATIONAL REFERENCE AMMUNITION