There are a few questions only on this site about this but none of them answer my question.

[Can cannonballs go through water?](https://physics.stackexchange.com/q/31151/)

[Why does a bullet bounce off water?](https://physics.stackexchange.com/q/23857/)

I find it hard to understand why bullets shoot through water at longer distances but stop in sand almost right away:

1. Both water and sand are made up of smaller droplets/grains and both are relatively heavy elements (sand is only 1.5 times heavier per volume). Water molecules are bound by Van der Waals force into droplets, sand molecules are bound by covalent bonding into crystals
2. At slow speed, I can put my hand through water and sand both. The droplets and grains can roll over and accommodate an object easily.
3. At high speed, an airplane crashing onto water will fall into pieces because water acts in this case like a solid, because the molecules and droplets don't have enough time to rearrange to accommodate the object. Same with sand.
4. Now in the case of a bullet, this argument seems not to work. In air, bullets reach speeds over 1800 mph. Bullets penetrate water, and can keep high speeds up to 10feet. On the other hand, bullets can't penetrate sand at all, they stop completely almost with no real penetration.

Bullets can keep high speeds up to 10 feet in water.

<https://mythresults.com/episode34>

Bullets in sand are completely stopped after 6 inches.

<https://www.theboxotruth.com/the-box-o-truth-7-the-sands-o-truth/>

Question:

1. Why do bullets shoot through water but not through sand?