The bolt may go out of headspace prior to the barrel being shot out.
Diemaco/Colt Canada has 5.56mm Chrome Lined CHF barrels that have lasted 20,000 rds and still retained sub 1.5" performance.
I would beleive that the Match CM barrels (Obermeyer or Kreiger at this point) that are much smoother than CHF barrels, and then chromed - would last that long given the lower velocity of the .308/7.62mm NATO loadings.
I’ve seen SR-25’s still be within headspace at over 15,000 rounds, but I would be very catiously gauging it at that point, as I have seen very heavily abused ones be very close at 7,500 rds.
One of the things, of many, we noted on the Battle Rifle PIP that hatched the SR-25 EMC, was that the bolt being cut that way, both retained more lubricant, and also was encumbered less by fouling and debris.
We made a decision not to put these intially in the Commercial guns. A lot of the imptovements for the government gun, where not going to be noticed as much in a civilian gun, we figured that we would introduce those at a later time, when we had an easier method of production.
My personal SR-25 EMC does not have the cuts, I would have liked them, but I don’t feel like I am screwed without them in a civilian setting.
I must admit that being a civilian and hearing that my gun is being built to a diff. spec might offend me as a potential buyer of the emc…I dont think its like that or anything, but the way it was phrased sounded a bit like that to me at least:)