If you mean +P, the difference is velocity.
A ".38 +P revolver" is simply a .38 Special revolver which is rated to fire +P loads. It's still a .38 Special, and the +P doesn't change the dimensions of the round itself.
It depends on how old it is. Needs to be examined by a gunsmith.
It's a .38 Special revolver. +P applies to the cartridge, and indicates a more powerful load than a standard round of the calibre. In this case, it would be a .38 S&W Special with a +P loading, hence .38 Special +P. You can fire regular .38 S&W Special cartridges through it. Whether or not it can fire +P or +P+ ammo, you need to read the instruction manual and find the manufacturer's information on this.
You need to contact Ruger for the answer to make sure the warranty isn't voided.
They are two different calibers, the 38 special round being a later invention. The 38 special should not fit into the 38 S & W chamber. But as the 38 special was not anticipated at the time the 38 S&W was first made, it can have a chamber that does fit the 38 special. As the 38 special is a higher pressure round, and comes in even higher pressure plus P cartridges, it is a bad idea to try to fire these in a 38 S&W revolver. It can crack or burst the cylinder among other things.
+P has more muzzle velocity
A pistol rated to fire .38 +P ammunition is still going to be a .38 Special pistol, and can use regular .38 Special ammunition. .357 Magnum revolvers are also capable of chambering and firing .38 Special loads - regular, +P, and +P+ included.
you can shoot standard 38 special rounds out of a firearm marked for 38 special +p
The .38 Smith & Wesson cartridge was created in 1876. It is a shorter, fatter, less powerful cartridge than the .38 Smith & Wesson Special, created in 1899 (they cannot be interchanged). The .38 Special +P is a .38 Special cartridge that is loaded to 10% higher energy than a standard .38 Special. The .357 Magnum is a longer version of the .38 Special that is loaded to MUCH higher energy than a .38 Special +P.
You can, but, you should not. The frame is not rated for +P
.38 special Stay away from the "+P" ammo
Depends on the pistol. If there's nothing about this in the owner's manual, or there is no owner's manual, you should contact the manufacturer for clarification on this matter. If you're unable to do this, a gunsmith should be able to determine this for you. .38 Special +P is .38 Special ammo, but with a higher powder content, which generates higher chamber pressures. Older .38 Special revolvers which were manufactured before the advent of the .38 Special +P cartridge did not have to be mindful of this when they manufactured their revolvers.