There is a rather large list of milsurp guns that are "dangerous to shoot", but very close to no substantiated proof to support the various claims. You know the:
- ones made with commie steel;
- guns missing the important third lug;
- anything Italian, Spanish or French;
- all Krags;
- etc.
I have done a bit of "proof testing" with Carcanos, including the dangerous

"Cooey (or Eaton) Carcano" and found them to be exceedingly strong, and even have a "Bannerman" Mosin that I have examined and then shot with impunity. A clever guy who goes by "Clark" on various boards has done an immense amount of proof testing on a number of milsurps and has been called an idiot and worse, and was actually banned on at least one board by the "Luddites" in control of it - all because of his proof testing (done at his own risk), and his outrageous practice of publishing his results.
With very rare exceptions (e.g. poor steel in low-number Springfields - and even then there are no reports of kabooms), there just is no published proof to base the labelling of any guns as unsafe. When called on it, claimants will admit they didn't actually see the gun, but will offer something like "I heard from a reliable third-party source whose name escapes me". Milsurp Folklore.
I am not saying that all milsurps are indestructible, just that the various claims that guns are weak are being based on hearsay at best. I would LOVE to see some proof - there just doesn't appear to be any (yet), and when someone like Clark conducts a test, the sheep refuse to acknowledge it. If anyone has important evidence, bring it on, but be prepared to defend it.
Original research seems to have died off. The Ackleys, Gibbs (not that those two's claims weren't full of $hit to some extent due to their commercial interests), Keiths and such seem to have no successors.