Re: 300 NORMA MAG ?
rifling twist should be 235 mm (1 in 9.25in).308 Norma Mags and .30-.338 Win. Mags (same thing, different headstamp) got about 1200 rounds of 3/4 MOA at 1000 yards as a long range prone match rifle burning 65 or so grains of powder pushing 200 grain pills out somewhat over...