After comments about large frame UU's I went and checked mine. And for the record, I bought the UU that was designed to fit on an Aeroprecision receiver, not the LaRue receiver. Again, part of my theory of why buy a $300 receiver when I can find one for under $200.
OP would lose his mind if he saw how the upper and lower match up. Visually, it is a disaster.
However, the upper and the lower lock up tight as a drum. No play whatsoever. And the gun shoots lights out, so no impact on performance.
Plus, LaRue let me order a suppressor at their reduced price ($400) about 2 years after I bought the upper.
But for those of you obsessed with how your AR looks, rather than how it functions, I have a suggestion:
https://www.amazon.com/Applicator-R...9Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=