The following specifications establishes material requirements and process procedures for Gun Kote. A coating developed for ordnance usage on equipment and weapons, providing excellent corrosion protection, abrasion resistance, and the lubricity to meet automatic weapon dry firing requirements after 60 days sea water immersion.

Applicable Specifications:

The following documents form a part if this specification to the extent specified herein.

Mil-S-3136 Standard test fluid, Hydrocarbon Mil-G-5572 Aviation gasoline, Grade 115/145 Mil-H-5506 Hydraulis Fluid Mil-J-5624 Jet Fuel, JP-4 Mil-L-6082 Lubrication Oil Mil-H-8446 Hydraulic Fluid, Non-petroleum Mil-R-81294 Remover paint, Epoxy System QQ-T-698 Cold rolled steel UU-T-106 Tape, pressure sensitive ASTM B117-63T Salt spray fog testing ASTM D-1654-61 Corrosion Protection ASTM D-870-54 DI Water immersion FTM 151A Accelerated salt spray (fog) testing

Material Requirements:

Component material used in the manufacturing of this coating consist of abrasion resistant corrosion inhibiting and lubricating solids dispersed in a suitable binder using a solvent carrier.

Baking/Curing

Coating shall be fully cured when baked as follows:

All colors 60 min at 150 degrees C

Appearance:

The bonded coating shall appear uniform in color, smooth free from cracks, runs, scratches, pinholes, blisters, bubbles, sags, and foreign matter.

Thickness:

The thickness of the coating shall be between 8 and 12 um unless otherwise specified.

Adhesion:

Place a strip of masking tape (UUT-106) firmly on the cured coating, with a quick motion remove the tape. Tiny particles are permissible, but the lifting of the coating to the base material is cause for rejection.

Thermal Stability:

The cured coating shall withstand exposure at a temperature of 260 degrees C for 100 hours minimum and 1000 hours minimum soak at -50 degrees C when tested for adhesion requirements.

Minimum initial oxidation temperature 460 Degrees C

Thermal breakaway @ 500 degrees C Minimum

Fluid Resistance:

>Coating shall meet requirements of Adhesion after immersion in the following fluids for time specified.

Mil-S-3136 Standard test fluid, Hydrocarbon 24 Hours Mil-G-5572 Aviation gasoline, Grade 115/145 24 Hours Mil-H-5506 Hydraulis Fluid 24 hours Mil-J-5624 Jet Fuel, JP-4 24 hours Mil-L-6082 Lubrication Oil 24 hours Mil-H-8446 Hydraulic Fluid, Non-petroleum 24 hours Mil-R-81294 Remover paint, Epoxy System 24 hours Trichlorethylene   24 hours Dow Corning DC-550   24 hours Nitric Acid   24 hours Hydrochloric Acid   24 hours Hydrogen Peroxide   24 hours Ammonia Hydroxide   48 hours Sodium Hydroxide NaOH 1 hours Sulfuric Acid H2SO4 3% 1 hours Sulfuric Acid H2SO4 30% 1 hours Sodium Bisulphide NaHS 3% 30 days Alkaline Cleaner, Highly Chelated (ANN-RO #101) @ 212 degrees F 2 hours

Corrosion Resistance:

The cured coating when applied to bare sandblasted (120 Nevada dry sand @ 30 psi) to cold rolled steel test panels conforming to QQ-S-698 shall pass the following test procedures with maximum of three (3) rust dots per panel.

ASTM B117-63T Salt spray fog testing for 1000 hours, minimum rating 9

ASTM D-1654-61 Corrosion Protection Minimum rating 9

ASTM D-870-54 DI Water immersion minimum 1000 hours @ 37 degrees C

60 Days sea water immersion

Impact Resistance

Minimum.375 in. deformation before loss of adhesion evidenced by cracking and peeling of coating on upset area of panel when struck with a .250 in. radius round nosed impact rod.

Dielectric Strength:

Minimum insulation with a 50 VAC applied, 1100 MEG OHM. insulation breakdown @ 500 VAC minimum applied to test specimen.

Abrasion Resistance:

Wear life when test panels tested on tabor abrasive with #cs10 wheel installed @ 500 gram weight minimum 235 revolutions (average of 3 test specimens) minimum 225 revolutions (low test specimen).