I actually put a stack of .30-30 cartridges in a polycarbonate tube about the size of a Marlin 336 magazine one time to prove this to a coworker. They DO NOT stack in a straight line under spring compression, in fact you can't force them stack that way. Invariably the bullet tips push off to the side of the case head above them as far as they will go, stopped by the shoulder against the magazine tube wall. I personally have loaded Sierra Matchkings for my .30-30s without any worry about chain detonation. Your mileage may vary.
That said, this may not be true of other cartridges such as .35 Remington or pistol caliber, and is definitely NOT true of the .45 ACP, which is one reason a levergun was never commercially chambered in .45 ACP although I know of at least one done by a gunsmith for a member of this board and I have performed a pump-action rifle conversion for myself.
There is, or was, a video on the utoob, possibly Taofledermaus or Mythbusters, who explored this topic and finally achieved chain detonation during an increasingly aggressive test using .223 cartridges which stacked exactly point-to-primer in a close-fitting tube. It took some effort to initiate the reaction (more than any slide-hammer effect from recoil), and was fairly dramatic in its results when it did go off, but generally that is out of the realm of the ordinary and certainly wasn't done with cast bullets. There may have actually been some instances of injuries due to chain reactions in a magazine tube, but I am not aware of the actual conditions that caused them or if in fact any have really occurred.