Can you get those in .50 caliber?
The 50-caliber BB guns can shoot down a helicopter and sink a battleship.
Can you get those in .50 caliber?
Once upon a time you could.
As I recall, .45 (about) and up caliber air rifles were used in the French & Indian and the American Revolutionary Wars.
They had compressed air charged bottles (like canteens) attached to the stock. They were used as sniper rifles, quite effectively by some accounts.
(If anyone has more recent knowledge than that from my own misspent childhood, then please embellish.)