what are these calibres like and who has used them for hunting?

Express - I shoot a .338 Lapua and just finished a .30-.338 Lapua. Both guns are set up as LR target guns, not deer rifles. They weigh over 18 LBS and both have muzzle breaks - something I would never put on a hunting rifle.

In my opinion, these cartridges are way too much horse power for general hunting purposes. To lighten one down so that it is transportable in the field would result in punishing recoil. In addition, these cartridges push bullets well beyond their ability to perform well on game. I would stick with .300 WinMag or Dakota, or .338 WinMag or Dakota. The Ultra Mags are fine as well, however, I would not purchase a factory chambering.

I have one of each. A Weatherby in 30-378 and a custom Ruger #1 in 338 Lapua. Both shot the same weight bullet at about the same speed with heavier bullets for the 338. I have only killed antelope so far. One with the 30-378 at 236 long paces and three with the 338 60 yards 337 yards and 125 yard Texas heart shot, all lasered. Did not has to look for or chase anyone of them. I will trade the 30-378 later this year and build a light weight 338-284 for walk in hunting