There ARE rifles and revolvers chambered for the 44 magnum cartridge. If the weapon is marked ".44 Magnum" then it can be used in that weapon. You should know that there are other .44 caliber catridges, and THOSE weapons (44 Special, 44-40, etc) cannot use 44 magnum loads.
This is the ammunition the gun is designed to fire, it is not hard on the gun.
If the weapon is chambered in 357 Magnum, you can fire the round in it.
As long as both the rifle and the revolver are chambered in .44 magnum you can use the same ammunition for both. I have a Henry rifle in .44 mag and a Ruger redhawk .44 mag and I use the same ammo for both. That's one of the nice things about that caliber.
The .22 magnum is more powerful, longer and a larger diameter than the .22lr. The magnumcartridge does not use the "heel seated" bullet of the .22 LR, and USUALLY has jacketed bullets. The full name is .22 WMRF (Winchester magnum rim fire) and they do NOT interchange with .22 LR. There have been a few revolvers built with two different cylinders to permit switching between LR and Magnum.
Shouldn't have any problems with revolvers, single shot firearms, and lever action rifles. However, a semi auto chambered in .357 (such as the Desert Eagle or Coonan Arms pistols) won't be able to run .38 Special.
No - neither a semi-automatic .357 Magnum nor a semi-automatic .357 Sig will. .357 Magnum revolvers can fire .38 Special rounds because 1: they feed from a cylinder which can accommodate the shorter .38 Special round and 2: unlike a firearm with a chamber, the cylinders in a revolver do not need to be headspaced.
The Ithaca rifles are rimfire. Most are .22LR, but there is at least one .22 magnum.
There are dozens of models of rifles and a few revolvers that fire the .17 HMR cartridge. Rifles in that caliber are made by Remington, Winchester, Marlin, Mossberg, Savage, Taurus and others.
Bullets travel at different speeds. Bullets from handguns and rifles can travel from a few hundred feet per second to several thousand feet per second.
No. You can only safely fire the correct caliber from each handgun. For instance, for a .40 caliber handgun, you can only fire .40 ammunition. There are some minor exceptions, mostly in revolvers. For instance, you can fire .38 special or .357 magnum from a revolver that will fire .357 magnum, but not the other way around.
The SA80 fires the 5.56x45 mm cartridge. This is one of the smallest calibers for center-fire rifles.
With few exceptions, no. Even with those exceptions, the cartridges are actually the same caliber, or a barrel change is required. .357 Magnum revolvers can fire .38 Special cartridges, and .44 Magnum revolvers can fire .44 Special cartridges. This applies only to revolvers, and should never be done with semi automatics, lever action rifles, or any other type of firearm which has a headspaced chamber. .40 S&W semi auto handguns can fire the .357 Sig (not the .357 Magnum) cartridge with a barrel change for the appropriate caliber. .22 Long rifle firearms can fire .22 Long and .22 Short cartridges. The .22 LR, Long, and Short cartridges do not generate sufficient chamber to pose a threat to the firer, even with a headspaced chamber. However, it can only be used as a repeating firearm with a tubular magazine - a .22 Long Rifle box magazine cannot accommodate the shorter Long and Short cartridges. Other .22 calibers, such as the .22-250 or .22 Winchester Magnum Rimfire, are not compatible. Firearms chambered in 5.56x45 or .223 Remington can sometimes fire the .22 Long Rifle cartridge with modification. Typically (as is often seen in AR-15 pattern rifles) the bolt carrier assembly will be replaced by a .22 Long Rifle firing assembly. Such kits are available for AR-15 pattern rifles and the Ruger Mini 14.