I had a terrific HW 66 in .17HMR then suffered a fizz and a bullet stuck 4 inches up the barrel. I replaced all the numbered batch of ammunition with new and suffered the same twice. No split necks. I had it bore scoped and sold it as I lost trust in the calibre. Hornady ammunition. As Alekd, QC needs to be addressed BUT, this was FOUR years ago and (some people are finding) the situation persists.
A shame as it was a great 175 yard vermin / 100 yard fox rifle and accuracy was always around 0.7 MOA.
What is going to replace it ? 17WSM - try getting the ammunition, 17 Fireball - try getting the ammunition, 17 Rem - only 40gn factory ammunition I believe, 17 Hornet - just received my ticket for one.