I also do not endorse rucking. Typically I only do one, maybe two a month and the farthest I typically go is 12 miles.
If you can ruck past 10 I feel like you could ruck past 50 miles if you had to. Like others have said save your knees and your back bc rucking is horrible for you r body.

thats why I am trying to row 25k/week and hopefully get over 50k/week in the next few months.