Hell no. .410 is not a gauge it is a caliber. True gauge is a measurement of the number of lead balls of bore diameter that constitute a pound. The .243 bullet is a lot smaller than the diameter of a .410 barrel. There are some .410's that can shoot 45 colts but not all can.
No, you cannot safely shoot a .45 caliber bullet from a .40 caliber handgun. The .40 caliber handgun is designed specifically for .40 S&W ammunition, which has a different casing size and bullet diameter compared to the .45 caliber. Attempting to use .45 caliber ammunition in a .40 caliber firearm could lead to dangerous malfunctions or serious injury. Always use the correct ammunition specified for your handgun.
No, the bullet will not seat.
no
how far does a 50 caliber sniper rifle shoot accuratly
No.
No.
You can from some, but they have to be designed to shoot both.
No
Although there are many variations, most AK47 shoot a ~30 caliber bullet (7.62mm).
No, it won't fit. The .45 caliber bullet is 0.45" in diameter; the .30 caliber bullet is .15" smaller. The brass is different size too.
No. A smaller caliber will either not fire at all, or will split the cartridge casing if it does fire.
Generally speaking, no. You can only fire the caliber for which the gun is chambered. There are some exceptions, but not many.