This thread has over 100 views and no replies. I don't want to give you bad info, so someone jump in if I'm wrong on any of this.
If you didn't already know, DPMS is owned by Freedom Group along with Bushmaster, Remington and some others. So the good news is 308 ARs made by these three companies are basically the same. Also, I’m not sure of the exact history and it can be a bore anyway, but suffice to say that Remington’s 308 AR, and Knight Armament’s 308 AR (SR-25 and M110) were/are both made with AR-15 compatibility in mind. Things such as stocks, grips, non-free-floating fore ends, trigger groups, and other parts are AR-15 interchangeable. Also, a good point is Bushmaster/Remington/DPMS’s 308 ARs will take Magpul's 308 PMAGs.
As for these internal parts you are asking about… I would consult DPMS.
Slow is Smooth. Smooth is Fast.