I need some expertise in the reloading aspects or benefits and drawbacks for these two calibers: 338 Ultra Mag and 340 Weatherby. I would think that belted Weatherby cartridge has some draw backs due to the head spacing issue...i.e.….little more finicky on accuracy, pertaing to the double radii. I am looking on sending this gun out ASAP to make this year's elk season. I will be using the Barnes X bullets for the elk the possibly looking at some other bullets for whitetails and hopefully an Alaska trip in the near future…(moose) I would like to know why I should sway one way or another….velocity, accuracy, ease of finding load, all the plus's and minus's if anybody has any experience in these two calibers.