I dropped my Nuke into my Buddy's ACC temporarily to compare the fit vs his Ultimatum Deadline (he was having issues). From what I remember, there weren't any notable issues with the Nuke. Mind you we didn't fire it or cycle any dummies through it, but as far as the drop in fit went, it seemed fine. Mine has lived it's whole operational life in a KRG Bravo with no issues, including with a Barloc installed. This would be with the current KRG backbone.
Only trigger I have experience with is the TT Special and have the 19lb firing pin spring installed. No light strike issues after 350 rounds using Factory Hornady and Federal match ammo and 205M primers in Alpha brass. This includes hunting down to 0 degree weather with blowing snow. Not the most helpful answers, but hope it helps nonetheless.
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