Daryl, I had the good fortune to grow up around a great bunch of enablers. They made sure I had work to pay for my shooting, and then made sure I had access to guns and ammo to fill my spare time. JB offered to let me try to wear out his .458 (and he knew me well enough to know I'd give it a serious try).

He had put about 200 rounds through the rifle, and I put another 1,000 or so factory-equivalent handloads through it. After that I kind of "Super-vel'd" it, loading bumped-up pistol slugs at absurd velocities.

That--several thousand 230 grain bullets at about 2,800 fps--was probably what killed the throat in the barrel. Group sizes at 100 yards almost doubled, even with factory loads. When the rifle was re-barreled about '87 or so, I sectioned it to look at the throat. The erosion was pretty bad for a bit more than an inch.

I've since become more cautious in my loading practices.