.358 Opinion...
The reason why they're rare is that the slight shoulder on the case wasn't always enough to maintain headspace when the firing pin hit the primer. Winchester didn't sell many. Let the collectors have them.
This advice comes via the late Jack O'Connor, normally a strong supporter of the M-70.
O'Conner's assertion (like much of what he wrote in my view) is ridiculous.
I've been shooting the .358 for near 30 years and have killed a stadium full of deer with it. Two last year alone. All were with handloads however.
Never had a misfire. I have brass still in service from when I started handloading this round in 1986.
In my view, the most limiting factor in the .358 chambering is the bullet type loaded. Simply put, the W-W SilverTip is not well regarded in many deer camps that I've hunted in. I assume others feel the same way. I think that if Remington had loaded this cartridge with their CorLokt slug, it's reputation would have been different.
Bullet selection is however, critical for optimum performance. I've used the old Hornady 250 grain, the Hornady 200 grain, and most recently the Sierra 225 Game King. Of all of these, the 200 grain .35 Remington bullet gave the best terminal performance, but being a round nose I went to the 225 Sierra as it is a spitzer. Where I hunt, longer shots are possible.
Suffice to say, I was not happy with the expansion of the Sierra spitzer. Last fall, one deer shot at 125 yards was quarter-to-quarter through and through and I had to leg that deer down and kill it off with my .22 after it fell into a gully. The other was 40 yards and the hit was in the center of the sternum. This slug traversed the deer completely, breaking the rear femur bone and lodged just under the skin.
Frankly, I expected more expansion. I still love the .358 and we have a BLR and two Ruger RS Carbines here, so we will still hunt them. But clearly, I need a better bullet. I think this, more than anything else, killed off the .358 in the Model 70 and 88.