348 grain on a yote? Im sorry but maybe i do not understand.. Are you trying to gut it out at the same time?

They should do good with the 1"48 twist. I have "60" 225 grain aerotip powerbelts coming in for my .45 rifle. Hope it shoots good with them.

I'd start out at 70 grains of Blackpowder and work it up from there. Whats your max range?