300 magazine is too short for 358, unless you use stumpy pistol bullets.
I was fiddling around with rechambering experiments in the 300 I eventually just sent to get rebarreled in 250. I did come up with one I called 358 Short, that fed ok, but because of the shoulder differences and the rotor, only 2 or 3 rounds would go into the magazine and feed reliably. It was just a 358 Win with the shoulder pushed back a bit, then the neck shortened down considerably. COAL came in between 2.580 and 2.595 with 200-225gr bullets.
Case capacity was a bit more than a 35 Remington, but considerably less than standard 358. Basically it would have been +P 35 Rem.
Last edited by zcm82; 10/12/21. Reason: addition
