How good are Frag Vests, what type of protection do they give and, will they stop pistol fire?

Quoted: How good are Frag Vests, what type of protection do they give and, will they stop pistol fire?

They stop frags.   Pistol fire?   No, probably - not rated for it.

bulky and a PITA. No ballistic protection other than stopping shards of hot metal from slicing you open.

Actually it depends on the vest.  Some will stop a pistol bullet.  IIRC most of them are rated to level 2A.  

Check out this link - http://www.theboxotruth.com/docs/bot15.htm.

Old Painless las a website - theboxotruth.com - where he tests these things.  Lots of great information there.  His frag vest stopped a number of pistol rounds that he fired into it.
As for rifle fire, they won't stop them, but may decrease the level of injury.


-K

If youre talking about the old PASGT vest, its between Level IIA and II.  The newer Interceptor is about equivalent to Level IIIA (the highest level of soft armor protection) w/o the plates.  Military vests are NOT NIJ rated however because they meet a different set of specs than are needed for LEO work

Quoted: If youre talking about the old PASGT vest, its between Level IIA and II.  The newer Interceptor is about equivalent to Level IIIA (the highest level of soft armor protection) w/o the plates.  Military vests are NOT NIJ rated however because they meet a different set of specs than are needed for LEO work

Exactly.  

The older PASGT are only 13 layers of Kevlar 29.  Just under a NIJ rated Level 2A vest would have.

The Combat Vehicle Crewman vests have 16 layers of Kevlar (though you can add more to the carrier).

The Interceptor uses Kevlar 129, the 4th generation Kevlar that is stronger than the 3rd gen Kevlar 29, and as stated is pretty much the same as an NIJ rated level 3A.

The SAPI plates are usually marketed as being about a level 3+ since they are rated to stop 7.62x39mm rounds which aren't on the NIJ test.

The military uses the V50 standard.  The velocity of a 17grain projectile will penetrate 50% of the time. The higher the better.