AR15 Service Rifle Heavy bbl definition

[bsaumph]

Rule 4.1.1c for M16/AR15-Type Service Rifle states:

No full-length heavy barrels are permitted. No portion of the barrel forward of the rearward location of the gas block or front sight tenon shall have a diameter exceeding .750”.

Does this mean a heavy barrel is defined by the latter sentence or is there some other definition of a "full-length heavy barrel"?

I have a Del Ton Alpha 320H I'd like to use