I think it's rifle specific. Case head separation is the normal failure mode for my Savage 99 .250-3000, I have had it happen dozens of times in that gun. I will point out that though that never once has it tied up the gun. The two pieces of brass are always connected by a remaining ligament of material, and both pull out cleanly. I only notice the issue when I go to pick them up. I've only used Winchester brass in it.
Take away the Savage, and I've had maybe 2 case head separations in anything else. Everything fails by split necks.
I hear lots of people say they lose most of their brass to loose primer pockets, but I have never experienced that, personally.
Then you're not loading it hot enough. lol I typically load for accuracy, but I might try to load for speed AND accuracy with my next hunting loads, see if I can't get 2900fps with a 150, or close to 3200 with 130s....
For hunting I'd strongly agree with Cosmic, use NEW brass. After all, how many rounds do you go through each season hunting big game??
If you're reloading for high volume practice or competition, some accuracy guys do it EVERY TIME.
My problem wasn't so much whether I had the brass, but rather the simple fact that I was already using some brass, and that particular brass was producing good groups. I hadn't even considered the fact that I'd be better off using 1F brass for my hunting loads for the reasons mentioned above.
I've decided to change to a different bullet (I was going to go with the 150gr Woodleigh but if I can't find them I might go with a 130gr Swift Scirocco II) so I'll have to do load development again, but once I find a good load I'll load up like 30 or 40 with 1F brass and then this rifle will be set for at least a few years.