I only work with factory loads, so I'm probably not getting 100% of the juice from my squeeze.
I don't shoot the 500yd+ distances that some of you folks do, and that may make a huge difference. For the ranges I work with, the factory loaded Hornady 168gr A-Max is pretty hard to beat. My precision .308s are a factory Remington 700 AAC-SD and a 16" LaRue OBR. I tested roughly 12 other factory match loadings and didn't find anything that was consistantly better than the factory loaded Hornady 168gr A-Max. For a laugh, the Prvi 'Match' 168gr HPBT was consistently 4+MOA and their bulk 147(?)gr Ball came in around 1.75MOA. The 168gr A-Max loaded by both Hornady and Black Hills were roughly the same at around 3/4MOA out of both guns as long as I did my part. Various companies with various other bullets were fairly close but on average they basically came out in a statistical tie. The Hornady 168gr A-Max was fairly inexpensive and I could get lots of it, so that's what I got.
I like the idea of having a round for 'hard' targets - much like what LE or .mil would refer to as a "barrier blind" round. I tried several and most absolutely sucked - Hornady Interbond, Remington Corelokt, even the fabled Federal TBBC - all of them were no better than 1.5MOA. One of the Federal loads was actualy on the plus side of 7MOA - it was so bad I shot a 20 round group to get a reasonable measurement with a break at 10rds for a 5rd A-Max group to make sure my gun wasn't fucked. When I was searching around on the Black Hills website for what they had to offer I stumbled upon their 180gr Nosler Accubond. Sure, why not.
Ok these things are fucking scary accurate - as in they will consistently turn in better groups through my rifles than any of the 'match' ammo I've fed them. I've probably got every bit of 1000rds through both of the guns combined since I started this last year and they were consistantly 3/4MOA guns if I was doing my part. With under 200 rounds of BH 180gr Nosler Accubonds through these guns I've turned in a (going off memory) .55MOA with the R700 and .61MOA with the OBR. I switched back to 168gr A-Max and they open back up to ~3/4MOA. Unfortunately they are expensive as hell, nearly impossible to get even before the crisis and a 180gr bonded freight train. If I didn't worry about significant over-penetration issues and could get them for a reasonable price, I'd shoot nothing but.