I have quite a few 55 grain bullets. I know I could try them and see if they shoot accurately.
It depends upon what you mean by "best". There's no reason the 55 grainers won't shoot just fine from an 8 twist, I've shot a gazillion 55 grainers out of my two 8 twist 22-250's. The heavier bullets will buck the wind better and give better long range performance but there's no reason to think they'll shoot any more accurately than the 55's. Overstabilization is a myth.
But bullet integrity is not. There are many thin jacketed 55 grain bullets that could deform due to being spun too fast and loose accuracy. Of course there are certain bullets that take being spun hard without issues.
I guess it could happen, but I've not seen it. The only bullets I've had issues with too much twist have been 39 gr. sierra blitzkings out of a 20 practical with an 8 twist, after the barrel heated up it would spin apart about half the bullets. If they held together they'd print tiny groups. Switching to 40 gr VMAX's stopped the problem and it still shoots great. I have two 8 twist 22-250's that get used on prairie dogs, one is on it's third barrel. Years ago I got a whole bunch of overrun 55 gr ballistic tips from Nosler shooters pro shop for a little bit of nothing and fortunately both my rifles shoot them great so that's what gets slung at prairie dogs. I've probably got enough to last the rest of my life. I don't push them too hard, about 3600 fps or so. I've shot other 53-55 grain bullets out of them with no problems but since I got all those the ballistic tips that's all they've been fed.
