I have gone through several barrels in 300WM, not only is the type of steel used important on lengthening barrel life, but so is the TYPE of powder used.
I also have a couple of hunting rifles, one CM, the other stainless. Both have had similar rounds fired through them, the CM barrel shows more haze cracking and the throat is eroded for a longer section.
I definitely believe stainless barrels last longer, and wide rifling also lasts longer, especially if you use double base powders, which run cooler with less gas than single base powder.
I have 2 barrels cut with the same reamer, one barrel had half it's shots with H1000 and then switched to RE25. The other barrel has only had RE25 fired through it, round count on both is within a dozen rounds, the barrel that had H1000 fired through it had to be set back while the other barrel has not needed to be set back yet.
Cheers.
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