Is there any practical role for the M4A1 barrel? This is called a "heavy" barrel by the military, but to civvies it is more of a "midweight" barrel.

Does it have much utility in military service? It was adopted in part because certain special operations units experienced failures with their Government profile M-4 barrel, but part of the reason for this might have been due to the RAS; use of a free-floating handguard takes some of the stress off the barrel.

So, does the M-4A1 barrel have any practical advantages over a lightweight barrel? Are there situations where carbines might have to be fired full-auto at maximum rates, or would the SAW or medium MG be enough to do the job, and the extra weight of the M-4A1 barrel be nothing more than an un-needed burden?