Had this happen to me on Ronnie. Brake material detached from the metal backing and wedged in the drum. When i stopped the stuff fell back and the wheel moved again, and then the same thing happened. Replaced shoes and all has been well.I can't see how wheel bearing adjustment, brake adjustment or brake wear could cause a wheel to suddenly lock up and then immediately be ok again.
The "one-way" brake line phenomenon can happen if a hose has perished internally to the extent that fluid can only pass through it under pressure. The same can happen with a damaged (crushed) pipe. However, in either case, the brake would not free off as quickly as described (and anyway, it wouldn't suddenly lock up. At most it would stay on at the same pressure as had just been applied).
The most likely thing to cause a brake to suddenly lock up, out of the blue, (without the brakes being applied), is that the friction material has detached from one of the shoes, turned around with the drum and wedged in between the other shoe and the drum. It may have broken up and dislodged itself (or was released when the wheel was turned the other way: did you reverse?) and then part or all of it wedged in again a mile later. The fact that it didn't happen again in the next 10 miles might have just been luck (that it stayed in a safer position) or it could be that either it broke up sufficiently that pieces were too small/thin to cause a problem, or (in extreme circumstances) that the friction material could be worn so thin and be so far out of adjustment to the extent that there's enough gap that the loose parts don't get wedged in. (I suppose it's also possible that the second one is now also detached and so they are turning together, rather than one loose one wedging into the other fixed one).
You might also possibly get a similar effect with a broken spring: loose parts inside the drum, getting wedged in, with the added effect of a shoe that is no longer held properly in its position due to it's spring being broken.
Please let us know what you find when you take the drum off.
I could not get drum off as no puller handy .I have since done another 60 miles, no problem, but have I just been lucky. Waiting to get hold of new shoes, before taking to bits, in case need to replace.I can't see how wheel bearing adjustment, brake adjustment or brake wear could cause a wheel to suddenly lock up and then immediately be ok again.
The "one-way" brake line phenomenon can happen if a hose has perished internally to the extent that fluid can only pass through it under pressure. The same can happen with a damaged (crushed) pipe. However, in either case, the brake would not free off as quickly as described (and anyway, it wouldn't suddenly lock up. At most it would stay on at the same pressure as had just been applied).
The most likely thing to cause a brake to suddenly lock up, out of the blue, (without the brakes being applied), is that the friction material has detached from one of the shoes, turned around with the drum and wedged in between the other shoe and the drum. It may have broken up and dislodged itself (or was released when the wheel was turned the other way: did you reverse?) and then part or all of it wedged in again a mile later. The fact that it didn't happen again in the next 10 miles might have just been luck (that it stayed in a safer position) or it could be that either it broke up sufficiently that pieces were too small/thin to cause a problem, or (in extreme circumstances) that the friction material could be worn so thin and be so far out of adjustment to the extent that there's enough gap that the loose parts don't get wedged in. (I suppose it's also possible that the second one is now also detached and so they are turning together, rather than one loose one wedging into the other fixed one).
You might also possibly get a similar effect with a broken spring: loose parts inside the drum, getting wedged in, with the added effect of a shoe that is no longer held properly in its position due to it's spring being broken.
Please let us know what you find when you take the drum off.