The effect is extremely noticeable at higher ranks. Out of curiosity, I wondered if corpses counted as containers for the purposes of this Perk. They DO, and you'll find way more ammo than usual from even melee enemies.

How does scrounger perk work?

With the Scrounger perk, you'll find considerably more ammunition in containers than you normally would. ... This has the same 75% chance of spawning as the original ammo leveled lists and both are not mutually exclusive, making it possible to find twice the ammunition.

Is scrounger worth it New Vegas?

Scrounger is a massively underestimated perk that almost anyone can benefit from. It is not as if ammunition is tremendously scarce in the game but if you are like 90% of players, you alternate between your "best" gun and second best gun to prevent yourself from running out of ammo.