Guns n Girls have reviewed the LWRC M6A2 SPR rifle along with some fantastic gun photography.
The M6A2 SPR gets its spiral fluting before going through the NiCorr treatment process. The fluting makes the barrel 20% lighter in weight and relieves any longitudinal stresses built up in the barrel. Those who have handled other gas piston AR15 rifles will notice a significant weight difference up front and that the SPR has a better balance.