Call of Duty: Black Ops Message Board  

if you using second chance, swap your pistol for another gun like the HK21. but if you get shot your soldier will automatic use a pistol?????.......... Weird

It's because you are not allowed to use a Primary weapon in Second Chance... Quite the same system as in CoD4, Mw2 etc...

Lets pretend he grabs a pistol off the ground...lol

what does a second chance pro do?

Makes you able to get revived by team mates , and you have more "down" time

Or more specifically, ups survival time to 30 seconds instead of just 10.

It's a feature that you, no matter what, will wield a pistol, regardless of your secondary. This makes it more appropriate as a perk that encourages usage of pistols and their attachments instead of far more useful items like the launchers or specials.