What benefit is there in purchasing a “heavy” CAR Buffer?

[massnee]

I need to pick up a new CAR buffer assembly and spring for my ar15.

Rock River Arms sells one they call "heavy". It is $23 as opposed to $10.50 for a regular one. What is the benefit in purchasing the "heavy" one?

This is for a RRA 16" Mid-Length.

 

[LoginName]

Probably none for an AR chambered in 5.56 (might be beneficial for ARs chambered in .308 or .458 SOCOM or .50 Beowulf).

 

[Big Daddy 45acp]

IIRC, a heavy buffer is supposed to slow down the cyclic rate on full auto. This improves accuracy and reliability.

Then again I may be wrong, as I often am, just ask my wife!