7.62x25 Tok.....where to start lol.
Probably best to just say that 7.62x25 Tokarev is a direct descendant,some would say a bastard child,of the 7.63x25mm Mauser.
It was created to be chambered in the Russian TT series of handguns,and used also in the famous PPSh41 submachinegun during WW2.
Tokarev TT mod.1933 pistol, left side view
Early production Shpagin PPSh-41 submachine gun, with drum magazine
As for ballistics,which is what you specifically asked about-
Some folks would call it anemic,which is odd,considering that,properly loaded, it delivers over 500 foot pounds of energy,and is well known to be able to penetrate soft body armor.
AP 3 (7.62x25mm FMJ)
That being said,it doesn't impress the big bore crowd,being that it is only .30 and weighs less than a .380 ball in conventional military trim.(Its typically an 85gr. projectile.)
In any case,its more than capable of doing the job that pistols are required to do,as penetration is definitely there (in spades),and most pistols it is chambered for are accurate enough for a good shooter to achieve good shot placement.
You can also find specially loaded ammo with JHP projectiles,if you like.
I'd actually suggest this whole heartedly if your interested in choosing this caliber for personal or home defense,as ball ammo will most definitely over-penetrate.
7.62x25 - Reed's Ammunition & Research, LLC
An interesting curiosity about the rounds terminal performance in ball format,however,is that it tends to yaw and tumble,rather than just "zipping right thru" as has been suggested-
85gr Sellier & Bellot FMJ
The best thing about it,at least right now,is that you can own a military grade pistol and plenty of ammo while on a strict budget.