There seems to be a whole lot of information out there on different loads/bullet weight, and I am having a hard time deciding what to go with. </div></div>
There are good-great loads in 155 gr through 190 gr range* with barrel lengths from 18" through 27" that shoot well in 308 with the only condition that barrel spins them fast enough. (*) some would argue up to at least 208, others up to 220gr.
So, you do a bunch of reading, decide to buy in on one particulat set of arguments (or another) and then use their philosophy to choose a bullet. Then from that bullet, you choose a primer from their recipie list(TRL), a case from TRL, and a powder and charge weight from TRL. Part of this deciding process is the analysis of the twist rate of your current barrel, your application, and your bullet selection.
Then you develop a load using OCW, OBT, Audette test,... until the load shoots well engouh for you. Can/fix/write-down the recipie, make as many as you want until you change:: jug of powder, case of primers, lot of bullets, set of cases.
Repeat until its time to put a new barrel in it, and go again. Precision reloading is a HOBBY, don't think of it as production, plinking ammo is a different story.
Currently there are arguments in favor of the modern 155 high BC bullets, arguments in favor of the reigning king of the hill 175 SMK, arguments for 190s an even 208s in 308 for 1300+ yards stuff.
The optimal bullet ,chargeweight, ... remains application dependent, the maximum effective range is similarly application dependent. So after a certain distance, the application will determine which of the myriad of good shooting loads is optimum. Generally in 308, this distance is 350-ish yards. A well placed 308 at 350 yards will cause the target to be DRT if you put it in the his vitals. A properly selected hunting bullet will have a larger margin of impact where the target goes DRT than a bullet chosen for 'printing paper', and a larger margin of error where the target does not get away and is dead close by.
Inside of 800 yards, there is "not all that much to argue about" (competition marksmanship). A skilled marksman with a well developed 155 loading is at little disadvantage to a marksman of similar capabilities using an equally well devloped 190; with the caveat that this is done inside 800 yards. Even the lowly 168 SMK is not so bad inside 800 yards. Beyond 800 yards it "all gets trickier" not just hitting the target, but interpreting/understanding what the pattern of impacts is trying to tell you about the loading, condition of the barrel, tune of the load recipie, read of the weather conditions, 'the shooter that day'.
So, you have a 1:10 barrel. This means you can shoot bullets as fast as 190 possible up to 22g depending on atmospherics and MV. The marginal added dispersion of a 155 being shot in a 1:10 barrel over the marginal dispersion of a 155 being shot in a barrel of same quality but in 1:12 twist will be measurable (as in:separated from the other noise) only by the very skilled.
