Well, I mentioned that tidbit reminiscing about how loud it was with the standard Made by Mattel buttstock that came with the issue version I fired for twenty some-odd years in service. With every single shot I fired, especially in a non-hostile environment like at the range, that "Sproing!!!" sound pretty much overcame the pop coming out of the pointy end. But then I pretty much blocked out the sound of the blast and most anything else when firing anyway. IDK, maybe it's the way I cradled the rifle or something unique to my style, but I always qual'd at least 38 out of 40 every time I was dragged out to the range so it wasn't like I was doing something weird or anything. Although what was unique about my style was that I wouldn't actually hold the handguard when firing, but rest the handguard on a clenched fist and either squeeze or relax my grip to get the final elevation sight picture just right the instant before firing. Worked especially well in the prone supported position.
Apologies to OP for going OT.