I’ve rigged up a system to force carbonate mini-kegs and they take 40 lbs of pressure with no problem, so I don’t think their ability to withstand the pressure is the issue.
On the one or two kegs that popped out into pointy kegs when primed with sugar, the beer was wildly over-carbonated. Wildly. It’s the once instance where I came close to injury in home brewing.
I’ve heard the same advice to “under prime” corny kegs, so I have to think there are other reasons. But I don’t know what those reasons might be.
It’s easy enough for someone who wants to prime their kegs to do a side by side experiment.
Many years ago I witnessed what happens to fully carbed mini-keg when you add in a bit of shaking due to a 4 hour road trip. Let’s just say, we didn’t ever use that keg again. It held but it didn’t sit flat anymore. 8)
The one i just checked said 130 PSI. It may vary by manufacturer, but yeah, it’s something really high. I don’t know about the mini-kegs though, I’ve never used them.
Not cornies. Mini-kegs. They are MUCH thinner steel, as they are technically disposable.
I’ve also pinged one out injecting it with a small CO2 cartridge, so their ability to withstand pressure is substantially lower than a cornie. The tap stayed in just fine and all that holds it is the barbed fitting, but the bottom popped out on the keg.