Easily plus P.
The real answer is to check the manual or take it to a real gun shop to be looked at by a pro.
If its in good shape, it will be fine with +P.
I've had 2 of the earlier Model 59's and they are great weapons.
You will have to call S&W to get a correct answer.
Yes
NO
yes, but better to use standard ammo. +P ammo shakes the pistol a lot.
1. It can, but, it is not advised. 2. It is stated by Smith and Wesson that the model 14-3, which is the third change of the model 14 can safely shoot plus P ammunition.
You can, but, you should not. The frame is not rated for +P
Ammo, imporper assembly, dirty
You must contact S&W to get a correct answer.
What it is chambered for. SHould be marked on the barrel. Have a gunsmith check it out.
9mm parabellum
You must contact S&W to verify
9mm