In that you are most probably correct. The 358 never really caught on but can't seem to die either. Too many diehard 35 caliber fans... and it's the short action round of choice in 35 caliber. Another rechamber I've been researching, and havent reached any conclusions about as of yet is from 35 Remington in the Marlin to 358. We know this will work in the 760 but will the 336 handle the increased pressure of the 358. It handles the pressures generated by the 356, the rimmed version of the 358, but supposedly the 358 is loaded to higher prssures. I had always just assumed the reason the 358 wasn't the original caliber Marlin went with was because of the pointed bullets normally loaded in the 358 and the possibility of a detonation in their tube magazine.. The 358 would surely generate enough recoil to make this a possibility.. Perhaps a spiraled magazine as in the M14-141 Remington would ease some fears??