I have two AR-10 rifles; one a Ar-10 /w std 20" chrome lined barrel the other an AR-10T /w 20" SS barrel. Both of these rifles easily meet the accuracy standard advertised by Armalite. With SMK in 168 and 155 gr the Std AR-10 shoots about 1 MOA or a little more with the powders I've tried (H4895, BL-C(2) and H335); the AR-10T consistently shoots 1/2 MOA with the same powders.
I've been trying to load up a good supply of acceptably accurate SHTF ammo with the large supply of Hornady 150gr. FMC bullets I've got on hand. In the Std AR-10 with the above powders and 150 gr Hornadys I can get an occasional 5 shots in to a 1-3/4" at 100 yards but more often than not I get 2 or three shots in 1-3/4" but the rest of the shots open group up to 2-1/2" to 3-1/2". The AR-10T does a little better with the Hornady 150 gr FMC but not a lot better.
I weighed a sample of 10 Hornady 150 gr FMC bullets and they vary in weigh between 149.9 grs to 150.4 grs. as compared to samples of SMKs I've weighed which vary no more than .1 grs.
I know this probably answers my question about the accuracy difference between bullets; but I was wondering if any body using relatively inexpensive bullets has gotten any better accuracy in their AR-10 rifles (particularly the AR with the std chrome lined barrel)?
Or, am I just beating my head against the wall?