In this video I find out the BC for my Air Arms S200 firing the Daystate Rangemaster Sovereign at 24 yards. For this I had already done the chronograph test at the muzzle, which averaged 575 feet per second. I then set up the chronograph at 24 yards to repeat the test. After this, using the Pyramyd Air Calculator, I was able to input the two different figures at muzzle, and at 24 yards to calculate the BC. Bellow are the links to the calculator, and Arken Zulus, which were used during the test.

Pyramyd Air Calculator:
https://www.pyramydair.com/widgets/?B...

Arken Zulus 520 R:
https://arkenoptics.uk/w5dgbn