JohnT,
Sorry, I have no idea why your rifle doesn't go bang. I have had that problem with some other individual rifles over the years (though not a BLR) and it is always depressing. I mean, a rifle that won't go bang is sort of like a bicycle without wheels. What's the point?
Thanks to everybody for the feedback. Am working on an essay about rifles OTHER than bolt actions, and am in general finding they shoot a lot better than most bolt-action addicts expect!