“Blessed be the LORD my strength,
which teacheth my hands to war,
and my fingers to fight:”
(Psalms 144:1)

“YOUR ARMS RESOURCE”
AR-10 vs AR-308

AR-10 & LR-308 Uppers are not exchangeable on these lowers.

LR-308, DPMS ETC:

Video Explaining difference:
Warthog 71
https://www.youtube.com/watch?v=ABqhtI3hxdc