The .300 Winchester has always struck me as a poor afterthought. Winchester belatedly decided to come out with a .300 short magnum after the .30-.338 and the .308 Norma Magnum were well established. They came up with a cartridge which is too long to fit in either chamber, but which has to have bullets seated well past the bottom of the neck in order to keep the OAL down to standard magazine size, which was the reason for the short magnum in the first place.

Moreover, the .300 Winchester Magnum has a neck which too short (.278" versus .318" for the .308 Norma Magnum; the .30-.338 is .299) In my book, a cartridge neck needs to be at least as long as the caliber of the bullet it shoots.

In a single shot target rifle, where loading to fit the magazine is not an issue, the .300 Winchester Magnum achieved a certain reputation at 1000 yards. Both the Army and the Marine Corps rifle teams used it in the 60's and 70's, but it is rarely seen on the firing line these days, where 6.5 and 6mm bullets reign supreme.

My favorite long range rifle in Africa was and is the .300 H&H, but were I to opt for a shorter cartridge, it would be a .308 Norma Magnum, not the .300 Winchester Magnum.