If gas were to escape at 50K plus pressure I doubt that a piece of plastic cracked or uncracked would keep the bolt shroud from flying off and I doubt seriously that a manufacturer would allow that design to be produced if that would be the outcome.
If you check the links, you'll see this is exactly whats happening. I've found three cases with just a quick check on the internet. It's not even that it only happens with handloads, in one case it was a S&B factory load. Design flaws happen, why do you think they have product recalls. Even Tikka makes mistakes (any one remember the stainless steel barrel problem they had), so why does everyone find it so hard to accept. The piece of plastic doesn't just keep the bolt shroud on,
it is the bolt shroud. Some guys say it's only cosmetic, and when it breaks off they'll keep using the rifle without it, which means the little protection it did offer is gone. Remember that that hot gas and metal particles will be travelling at high speed directly towrds your open eye, and tell me if you still feel it's such a great design.
