"Safeties"???? Why I carry hot chamber only when quite necessary. And yeah - operator error.
My first year in Alaska, hunting, I had 3 Redfields go south on me in a month or 6 weeks. Have never used Redfields since. I suspect QC has improved since, but fugem.
Switched to Leupold, Burris, the better Tascos, and a Weaver, and have had no problems with any scope in the 50+ years since.
As to the actual rifle failures, my .338WM left it's bolt home alone once. And the Senaca forgot it's powder back in Fairbanks on a sheep hunt and got left in the truck in favor of a .270. Sly bastids!
I acquired a 725 found in a busted up sled out of Anaktuvik Pass, and it failed to go off on a cold weather shot at caribou after I cleaned it up. The replacement fp spring was a good 3/4 inch longer than the one I found in the gun. The pitting on the striker shaft probably didn't help any either.
The extractor broke a year or two later while sighting it in at the Cody range, on my way to my 2nd CO elk hunt. It was my son's permit, so I didn't really need to carry a back-up anyway. I used it the next fall that way on a caribou hunt. Extraction was a little slow, but effective. After the shot, tip the muzzle to the sky, open the bolt and bang the side of the rifle with my hand- empty case fell right out. A 700 extractor, contrary to some peoples' expertise here, works perfectly, 725 extractors being nearly unobtainium.
I had my Savage-Fox SXS double on a mallard coming off a farm pond in Montana. No idea why, has never done it since, but that bird came down dead! And no, I didn't have fingers on both triggers, only on the rear one.
I would guess that the most common failures are due to crud, or hunting in freezing weather and icing/gumming up. Mechanically, probably striker, sear, trigger interactions, after "safeties". (OK- that was easy, what else is there?!
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