Ive shot one, but it wasnt mine. There was a time when the the 350/6.5 case was necked down and up from 22 to 458. Ballistically it is very close to the 06 case, slightly more capacity in general. I built 7mm and 338 versions, both were a little faster with same bullet weights than their 06 based cousins. The 7mm version was practically identical to the 280 ackley I had at the same time. I liked them. - dan