Ed L., good to meet you. I have come across that article and read it some time ago. I actually have it bookmarked and refer to it from time to time. Nice write up. What I've found about my particular ACC is that it seems to prefer 168gr over 175gr loads. Of the 175gr loads, I get the best accuracy and most consistency out of the Fiocchi 175gr SMK. Suffice to say I haven't tried everything available out there and there might be something else my rifle likes, but short of reloading my own (I don't yet) I think I would be hard pressed to find COTS ammo that outperforms the Sig 168gr OTM for my rifle. FGMM does okay in mine. I've tried both the 175gr and 168gr SMK and they both average between 1.1 - 1.5 MOA for me. I should add that the last groups I shot were suppressed, so that might have contributed to the increased accuracy to some degree. I haven't done a side by side with and without a can, but maybe I'll be able to within the next couple weeks. Given that these rifles were never intended to be sub-MOA rifles, I'll take the results I'm getting and roll with it.
ETA: Leupold MK5HD 3.6-18x44 CCH w/ offset Aimpoint T2 - all shots were taken from the prone using the bipod and bean bag for rear support.
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