Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

I think both are very good depending its use!
Bow and Arrow: LBS = draw weight and Inch = draw length
Guns: .50 Caliber - sounds better that 12,15 mm
       or .357 .44 Magnum much better that 9 or 11 mm
Velocity: fps feet per Second better than meter/second
Weight: 15 grains are 1 gram - it is finer

and I like Inch thread - they are stronger!

Better keep both worlds also for the future

Arnold