Castrol Brayco® 300 is a blend of highly refined petroleum oil with suitable additives which provide corrosion prevention, oxidation resistance, and freedom from galvanic corrosion in brass-steel bimetallic systems. The viscosity is similar to a light machine oil. Castrol Brayco® 300 is a water displacing oil for general purpose applications at low and medium temperatures (-70ºF to 300ºF).
Uses Castrol Brayco® 300 is designed for the lubrication and preservation of small arms, automatic weapons, and fuse mechanism applications, especially where a low temperature, water displacing oil is desired. It may be used to protect unpainted metal surfaces from the effects of indoor storage for periods of three to six months, after which it remains readily removable. Castrol Brayco® 300 will also protect magnesium and aluminum against corrosion at low and medium temperatures (-70ºF to 300ºF).
|TEST METHOD ||DESCRIPTION ||MIL-PRF-32033 REQUIREMENTS ||RESULT |
|D287 ||API Gravity, degrees ||Report ||28.4 |
|Table 3 ||Specific Gravity @ 16°C/16°C (60°F/60°F) ||Report ||0.8849 |
|Table 8 ||Pounds Per Gallon @ 16°C (60°F) ||Report ||7.368 |
|D1500 ||Color, ASTM ||7.0 Maximum ||4.0 |
|D97 ||Pour Point, °C (°F) ||-57 (-70) Maximum ||-57 (-70) |
|D445 ||Viscosity, cSt |
@ 40°C (104°F)
@ -40°C (-40°F)
@ -54°C (-65°F)
|11 Minimum |
|D92 ||Flash Point, COC, °C (°F) ||135 Minimum ||142 (285) |
|D91 ||Precipitation Number, ml ||0.05 Maximum ||0.01 |
|D972 ||Evaporation Loss, % wt |
22 hours @ 100°C (212°F)
|25 Maximum ||11.2 |
|FTM 5308 ||Corrosion-Oxidation Stability, |
168 hours @ 121°C (250°F)
Corrosion, Pitting, or Etching
Wt Change, mg/cm2
Change in Viscosity @ 40°C (104°F), %
Change in Neutralization No.
Insoluble Materials and Gum
-5 to +20
|D130 ||Copper Strip Corrosion, 3 hours @ 100°C (212°F) ||2a Maximum ||1a |
|FTM 5329 ||Humidity Cabinet-SB Panels - 192 hours ||Pass ||Pass |
|FTM 3007 ||Water Displacement |
|FTM 202 ||Low Temp. Stability, 72 hours @ -54°C (65°F) ||Pass ||Pass |
|FTM 5322 ||Corrosiveness, 10 days (240 Grit) ||Pass ||Pass |
|Spec ||Film Characteristics ||Pass ||Pass |
|Spec ||Removability ||Pass ||Pass |
|D4172 ||Four-Ball Wear-Test, AWSD, mm ||1 Maximum ||0.7 |
|Spec ||Workmanship ||Pass ||Pass |
Health, safety and environmental information are provided for this product in the Materials Safety Data Sheet. This gives details of potential hazards, precautions and First Aid measures, together with environmental effects and disposal of used products. castrol will not accept liability if the product is used other than in the manner or with the precautions or for the purpose (s) specified. Before using the product other than directed, please contact Castrol for consultation.
Castrol Brayco® 300 may be applied by brush, dip, swab, spray, or squirt can.
Depending on the method of application and surface geometries, Castrol Brayco® 300 will cover 1,000 to 3,000 square feet per gallon.
For water displacement, it may be applied by these same methods. Displaced water should be removed from dip tanks at suitable intervals.