What does a bullet hitting kevlar sound like?

Question’s pretty much in the title. In the movies it seems like bad guys are always fooled when they shoot someone wearing bullet-proof vests. Doesn’t the bullet make a different sound when hitting kevlar? Is the sound loud enough to notice? Thanks for the help.

I’ll have to WAG and say that with the speed of the bullet, any sound would be cancelled by the rifle report. But now I’m curious.

We shot up some old (and unoccupied!) German kevlar vests and helmets a while back, using a variety of rifles at 200 meters, and various pistols at 25 meters and under. We shoot at a fairly ‘wide open’ range, with little or no echo. We did not hear anything unusual (not even at the pistol range, when at under 10 meters), other than our friend screaming when we let loose with the .300 Win Mag while he chatted on the cell phone. Not scientific, since we were not listening for anything unusual, and we all (except for Mr.Ihavetotalktomygirlfriendallthetimeevenifweareattherange) had our hearing protection on whenever shooting.

If you are the one wearing the vest when the bullet hits it, it sounds a little like this:

Just a reminder that Kevlar® is a registered trademark, owned by DuPont, not a generic word.

I’ve shot all kinds of kevlar. Hard helmets and shin guards to soft vest n such. I’ve never heard anything different. . . The round is pretty fast and loud, so anything it hits under a couple hundred meters will be hard to identify.

… except for steal which can still be heard at 25 meters.