I bet that everyone heard about Shells Rain mod made for Fallout 3 by Ginnungagap. This mod does the same thing, but here it comes with 5 different versions to let you better adjust your tastes and performance.

This mod simply increases the duration and amount of shells left on the ground after you shoot with a gun.


Vanilla stats are following:


Duration - 5 seconds

Visible Range - 512 units

Amount - 25 shells



Duration means how long it lasts before it disappear from the ground.
Visible Range is the maximum range when you can see shells, shown in units (21.3 units are 1 foot, 64 units are 1 yard, 70 units are 1 meter, etc.)
Amount is the number of max amount of shells on the ground, if you pass the limit the previous shells will start to disappear.



My mod comes up with 5 different plugins to let you use it both on weaker and stronger machines.



Very Light:

Duration - 1 minute

Visible Range - 1024 units

Amount - 500 shells



Light:

Duration - 10 minutes

Visible Range - 2048 units

Amount - 1250 shells



Medium:

Duration - 1 hour

Visible Range - 4096 units

Amount - 2500 shells



Heavy:

Duration - 12 hours

Visible Range - 6044 units

Amount - 5000 shells



Very Heavy:

Duration - 24 hours

Visible Range - 10000 units

Amount - 10000 Shells


You can find mod here: http://www.newvegasnexus.com/downloads/file.php?id=37867


Enjoy