.4005 inches.
In excess of a mile.
Assuming the question is in regard to firearms and ammunition, you can read the "caliber" of a round as a decimal how wide the bullet is in inches. So a .40 caliber round is .4 inches wide, or about 10.16 millimeters wide. A .45 caliber round would be .45", so a little bit fatter than the .40 caliber round. The caliber doesn't tell the whole story of a round though, it doesn't say how long the bullet is, how heavy, how big the casing behind the round is, how much kinetic energy is hits with, etc. The .40 S&W round has an average of 425 ft/lbs of energy right at the muzzle, while the .45 ACP, a "bigger" round, has about 400 ft/lbs.
No. 9mm and .40 are not interchangeable.
.40 Smith & Wesson is a 10x22mm cartridge, whereas the .45 ACP would measure 11.65x23 in metric measurements. The .45 is a larger round, and also a much slower round.
http://www.industrial-enclosures.com/html/conversion-mm-inch.html
my opinion is the 45 ACP round has more knock down powder then the 40 caliber
no, a 45 caliber is way more powerful than a 40 caliber Actually, it depends. The following is copied from another answer of mine: The muzzle energy from a .45 caliber round can vary between 350 to a little over 500 ft-lbs, with velocites from about 850 feet per second to over 1000 FPS. The .40 caliber round can range from about 480 to about 570 ft-lbs of energy with velocities ranging from about 1000 FPS to about 1400 FPS. So, in short, it depends on the specifications of the particular cartridges you are comparing.
It depends on several factors, but a good rule of thumb is "about a mile."
The muzzle energy from a .45 caliber round can vary between 350 to a little over 500 ft-lbs, with velocites from about 850 feet per second to over 1000 FPS. The .40 caliber round can range from about 480 to about 570 ft-lbs of energy with velocities ranging from about 1000 FPS to about 1400 FPS. So, in short, it depends on the specifications of the particular cartridges you are comparing.
The 9mm round measures .356 inch in diameter. a 380 is 95 gr 9mm 124gr 40 is180 gr 45 is 230 gr
The .40 is a larger diameter round. The projectile has a dimension of .4005, versus the 9mm Parabellum, which has a dimension of .356. Of the two, the .40 is the more powerful cartridge.