You'd have to first show there's actually early barrel burnout. Which is almost impossible to do without some pretty extensive data.
The only people that would even have remotely close to that amount of data would be someone like
@Frank Green who has already informed us that he has seen no such change from any high volume and/or professional use customer which would indicate there's an issue he needs to look into.
All good.... just shortened up your quote some.
Here are some numbers for you all....and being as 243win was mentioned (I didn't go back and read everything) I'll start with this one.
On a ammunition pressure test barrel.... rarely does a 243win make it I'll say past 800-900 rounds.
Same with a 300wm p&v test barrel. Most are getting pulled at about 800-900 rounds. Rarely do they make it past say a 1k rounds. If they got one that went 1200 that is getting out of the norm.
6.5CM on a p&v test barrel about 1700 is tops. If they got 1900 rounds out of one they milked it pretty good. Compare this to a 6.5PRC where they have get anywhere from 400 to 900 rounds. An average is 650 for this round.
I forget what was a normal for a p&v test barrel in 308win but I want to say it was around 4k. The 308win round for bore size is about the perfect relationship. It's very easy on barrels. Take that 308win and neck it down to 6.5mm or 6mm and you can see what happens above. Same thing happens when you take that 30cal barrel and chamber it in 300wm.... your basically doubling the amount of powder that goes down the bore.... which in turn leads to a shorter barrel life.
Any of the big 30 magnum rounds like 300wm, 300 Norma etc... looking at it from a accuracy point of view (not a pressure and velocity spec point of view).... I'll say 1k tops. If you got a 1k out of them that was great.
300 Norma pressure and velocity test barrels where they are trying to meet a .65moa accuracy requirement with box ammo (I think that is for either five or ten... 10 shot groups) they are pulling the barrels 500-600 rounds. After this round count they are on borrowed time so they don't want to trust the barrels anymore and will put a new one in service. They are going thru 10 barrels a month in this caliber.
Accuracy testing/shooting? First off you have to set a limit for your accuracy requirement. Just like in the example I listed above for the 300 Norma.
Your accuracy requirement (note I'm leaving out pressure and velocity here) can be way different in regards to what you get for barrel life.
I've gotten back barrels in 308win chamber that was strictly used for accuracy testing of bullets. I've gotten back not just one or two etc... but a bunch. Typically I cut them apart and use them for training tools at the sniper school houses. Anyways I have barrels with just shy of 10k rounds, 11,xxx, 13,xxx, 14,560 see attached pic never mind I'm having trouble uploading the pic.... sorry) and just earlier this year two barrels went 19k and 21K+ rounds before they would no longer hold .5moa or better. The normal accuracy test for bullets is five 10 shot groups and cleaning after every 50 rounds fired. If they are pushed for time and this applies to 308win only they will shoot as many as 150 rounds in between cleanings. Compare this to 6.5CM and usually the most they will get out of a barrel is 3k rounds and sometimes not even that.
This data is from test barrels being shot in controlled conditions with proper maintenance.