This post is a major Your Mileage May Vary (YMMV) project
The Why: I received my 6.5 Creedmoor Ultimate Upper kit but have no idea when the large frame lower will arrive.... I could have ordered a DPMS format large frame upper which would have possibly rendered this whole project moot. I didn't for fear of wandering from the LaRue standard (M110) "if it ain't broke don't try and fix it". Until the LaRue lower arrives I am dead in the water as I don't own any other LaRue rifles.
I'm unsure of the takedown pin hole size and layout differences between a UU LT-10 and other LT-10 but for those who clamored for an option to buy a lower only for your Stealth uppers etc... perhaps this is an affordable option....
Stag Arms released their first AR-10 this year, didn't hear about it? Yeah I know , hard to keep up these days...
The link to Stags design page explains the following:
https://www.stagarms.com/stag-10-rifle-information/
* Proprietary parts - ugh yeah I know I know....
* M110 slant but DPMS part compatibility
* Tension Screw from lower up to Upper (internal)
So far as I know the proprietary parts are , screw in bolt batch pin and takedown pin/detent, specifically the rear
Things left to try
It's apparent that the LaRue lower parts kit isn't compatible with the Stag lower . This was a wish, hope, and a prayer as id like to shoot my new UU Creedmoor.
So I have a Stag 10 lower parts kit on order
I suspect all will go together fine but I'll update here to speak to function... my guess is the .277" pin size of the Stag is "a thou" smaller than the LaRue upper pin size so I'll see how much play there may be .
YMMV