AGW Airgun Calculators & Conversions PSI ↔ BAR ←PSI: :BAR→ Yards ↔ Meters ←Yards: :Meters→ Feet/sec ↔ Meters/sec ←Fps: :Mps→ Grains ↔ Grams ←Grain: :Gram→ Inch ↔ mm ←Inch: :mm→ Foot-pound (ft.lbs) ↔ Joule ←Fpe: :Joule→ Energy (Metric) ↔ Joules (J) M/sec: Gram: :Joule→ Energy (Imperial) ↔ Foot-pound (ft/lbs) ft/sec: Grain: :ft/lbs→ Joules (J) ↔ M/sec Joule: Gram: :M/sec→ Foot-pound (ft/lbs) ↔ fps ft/lbs: Grain: :ft/sec→ Airgun Cylinder Fill Calculator NOTE: All variables must be entered in order for the fill calculator to work properly.Scuba/Divers Cylinder Pressure must be greater than Airgun Fill Operating Pressure. SCBA/Divers Cylinder Capacity: :ft³ Scuba/Divers Cylinder (Gauge) Pressure: :psi Airgun Fill Operating Pressure? :psi Airgun Cylinder Capacity: :cc Refill airgun when it reaches what pressure? :psi Approximate number of refills: