I see in your post you say mostly? I truely love Sierra Gamekings in 308 and I think the price is the same. Yes you can use those bullets marked for 30-30 and you don't have to push the bullet down to the cannular (spell check) either, but I think you will see a difference in accuracy that may be unacceptable past 75-100 yards with the 30-30 bullets. The shorter bullets do not like goingfast in my experence, although the 308 and 30-30 have similar twist usually 1-10 they just don't stabilize as well. I don't think there is any difference in mushrooming performance that justifies using flatnose 30-30 bullets over the Sierra Gamekings andInterlocks, stay away from SST's though they don't seem to mushroom well in my 308 but are pinpoint accurate. Good luck and remember this is only my opinion, not everyone or anyone will agree.