What are the effects to a bullet of passing through thick clothing before hitting a bad guy? Will that stop or slow down bullets considerably? Will it clog-up hollow points and prevent them from expanding?

We have several inches of cloth clamped to a cardboard holder in the Box O' Truth, just to keep it together.

Then, a milk jug of water to catch the rounds that exit. Then three pine backer boards, in case the jug doesn't stop the round.

The cloth includes 2 layers of blue jean material and then several layers of terry cloth towels.

I realize that there would be an almost infinite number of variables, this is just a common example of thick clothing.

First, a .22 LR from a pistol.
I shot a CCI Minimag HP.

It went through the clothing and through the water jug and embedded itself into the first pine board.

I dug around the bullet to help you see it.

It did not expand, but was slightly sideways in the board.

Then the mighty .32 ACP from my Keltec P-32.

Tman caught me in full recoil.

Just kidding. There was very little recoil.

We shot a Federal Hydrashock.

The round went through the clothing and water jug and was in the first pine board.

I dug it out to see it better.

This is it.

As you can see, it did not open up at all.

This was puzzling, as we have shot water jugs before with this round and they expanded perfectly.

How about a 9mm JHP.

I used a 115 grain JHP out of a Beretta 92FS.

It went through the clothing, water, 3 pine boards, and somewhere beyond.

We were unable to recover the bullet.