"Powerful" is somewhat of a subective term, but the answer is yes. 5.56 is a rifle cartridge and 9mm, assuming you mean 9mm parabellum, is a handgun cartridge. Under normal circumstances, bullets fired from rifles will have more velocity and more muzzle energy than bullets fired from handguns.
556 * 556 = 309,136
why you asking me 556-thousands = 556/1000 = 0.556 as a decimal
70% of 556 is 389.2. Which means that 166.8 is 30% of 556.
It is: 556 = DLVI
556 - 223 = 333
5.56 hands down.
Yes there is a difference. They are physically the same size casing, but the 556 military rounds' chamber pressure is ~10,000 psi higher then 223. Military rifles generally have chambers with a different throat configuration than normal sport 223 rifles. This being said, I would not recommend shooting 556 unless your rifle was designed for the higher pressures.
556
556 * 556 = 309,136
556 = 55,600%
why you asking me 556-thousands = 556/1000 = 0.556 as a decimal
70% of 556 is 389.2. Which means that 166.8 is 30% of 556.
556
It is: 556 = DLVI
563 + 556 = 1019
556 x 2 = 1,112
556 - 223 = 333