556 green tip Winchester celebrates its commitment to American freedom with the USA VALOR™ ammunition series. From World War I through modern day deployments, Winchester remains steadfast in its support of U.S. Warfighters as the largest small caliber enterprise in the world. Your purchase of Winchester’s USA VALOR™ Series helps support Folds of Honor.

Specifications for Winchester USA VALOR 556 green tip 62 grain Green Tip (M855) Full Metal Jacket Boat Tail (FMJBT) Brass Centerfire Rifle Ammunition:

Features of Winchester USA 556 green tip 62 Grain M855 Green Tip FMJ Centerfire Rifle Ammunition:

• M855 Green Tip bullet
• Reloadable brass
• Portion of proceeds from the sale of every box go to Folds of Honor

Package Contents:

• Winchester USA Valor 5.56mm 62 Grain M855 Green Tip FMJ Centerfire Rifle Ammunition, Bulk Case Box of 500 rounds

Cartridge dimensions

The 5.56×45mm NATO has 1.85 ml (28.5 grains H₂O) cartridge case capacity.

5.56×45mm NATO maximum NATO cartridge dimensions. All sizes in millimeters (mm).

The rifling twist rate for this cartridge is 177.8 mm (1 in 7 in), 6 grooves right hand twist, Ø lands = 5.56 millimetres (0.219 in), Ø grooves = 5.69 millimetres (0.224 in).

According to STANAG 4172 and the official NATO proofing guidelines the 556 green tip 500 NATO case can handle up to 420.0 MPa (60,916 psi) piezo service pressure. In NATO regulated organizations every rifle cartridge combination has to be proofed at 537.5 MPa (77,958 psi) to certify for service issue.

STANAG 4172 defines the Belgian ball cartridge SS109 as the NATO reference cartridge and adds a considerable number of technical requirements like a minimum pressure of 88.0 MPa (12,763 psi) at the gas port 280 millimetres (11.0 in) down the 508 millimetres (20.0 in) long standard proof barrel and primer sensitivity that are not defined by civilian C.I.P. and SAAMI ammunition rulings and recommendations.

The NATO military alliance uses a NATO-specific recognized class of procedures to control the safety and quality of firearms ammunition called NATO EPVAT testing. The civilian organisations C.I.P. and SAAMI use less comprehensive test procedures than NATO.

The NATO Manual of Proof and Inspection AC/225 (LG/3-SG/1) D/8 stipulates 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. Over pressure of 25% means 25% in excess of the service pressure resulting for the 5.56×45mm NATO up to 430.0 MPa (62,366 psi) (P_max) piezo service pressure.

The service pressure is defined as the mean pressure generated by the service cartridge at a temperature of 21 °C (70 °F). Such a high pressure proof is conducted with both the weapon and ammunition conditioned to an ambient temperature of 21 °C (70 °F).

Each weapon will be individually tested, from an ammunition lot that produces a minimum corrected mean chamber pressure. The corrected proof pressure requirement (service pressure (P_max) + 25%) for the 5.56×45mm NATO like the STANAG 4172 is 537.3 MPa (77,929 psi) (PE) piezo pressure. This pressure has to be recorded in a NATO-design EPVAT barrel with Kistler 6215 transducer, HPI GP6 Transducer or by equipment to C.I.P. requirements.

The US SAAMI lists maximum average pressure (MAP) for the .223 Remington cartridge as 55,000 psi (379.2 MPa) piezo pressure with deviation of up to 58,000 psi (399.9 MPa).