As Dennis stated, as the bolt goes to unlock, the entire bolt face with ejector and extractor is rotating on the back of the case, and the case bound to the chamber wall until the bolt actually starts to come back.

Now what I am seeing is that you have three problems going on, and this may just be ammo related alone (powder being used for the load with a longer dwell time, which increases the gas pressure that the Gas system sees through the system.

So on that note, first start off by checking the rim relief section of the extractor.  Chances are your going to see a nasty bur, and what is cause the scrap to the rim (as the bolt goes to rotate on the fixed case still pressure bound in the the chamber).

On the ejector, might want to give a quick check for a sharp bur on the face edge, but all in all, does not look that bad considering.

Blow primer, this could could be coming from a few places, but best bet, we are talking a new Auto chamber on the tight side, compounded with ammo really suited for a bolt action rifle instead, and maybe why you are seeing over pressure problems here.   If you just have to run factory match, then try out a box of Fed gold instead. Fed had teething problems as well with their match ammo in the auto, but after changing the gun powder being used (speed the burn rate up a bit), resolve the over pressure to the gas system problems.
Note, the slower the burn rate of the gun powder being used, the closer that it puts the peak dwell rate of the pressure spike towards the gas port, all the while, the ammo still within normal over all pressure rates.

As stated, do check for any burs on the ejector and extractor, and as for the Over pressure to the round/gas system, before going this far with a replacement adjustable gas block, do try Fed gold match ammo.

If the problem persists with the Fed ammo, then get RRA on the phone, since your chamber may be too tight, and what is causing the over pressure problems of the ammo itself in regards to actual working pressures (read if your blowing primers out of ball ammo as well, then it not just the gas system pressure, but actual working pressure as well.
Note, to read if the rounds are going over pressure in themselves, then read the spent primers in the cases that still do have the spent primer intact.  If the round is going over pressure, then the primer will be close to, if not completly flatten out to the edge of the primer,

Primer on the left is reading over pressure, while the primer on the right is reading normal.

A heavier buffer or stronger buffer spring will slow down  the unlock cycle.  This allows the residual pressure in the barrel to drop down a tad before the bolt goes to pull the spent cause out of the chamber.  Here, if the extractor was bending the rim of the case, or it just a mater of slowing down the unlock due to slower than normal gun powder being used,  I could see some merit going this way.

But it comes back to check pressure signs of the spent cases, and if the problem is the ammo going over pressure to begin with, then that needs to be resolved first (chamber problem).  Remember, we have the over all working pressure of the round foremost that has to be within spec, then the Dwell of the  gun powder burn and how closer it gets to the gas port more than normal, where we can tweak the unlock speed to resolve if the unlock is too fast.

Dennis2313, let break this down to two different working pressures.

First is the over all working pressure of the round itself.  Since we are talking 308, then SAAMI PSI 62,000.


Faster burning powder will acheive this top over all pressure spike faster down the barrel than say slower burning powder, but both can produce a working pressure of 62K.  Granted that the top of the pressure curve spike point may only be a inch or two difference down the barrel, It's this dwell/top of pressure curve spike location that plays back into how much the barrel gas port/gas system will see in pressure.  I Don't have graph in front of me, but the difference in say 150 ball ammo, to Hornaday match ammo could be in the range of 10K or more at the gas port, although both are working at 62K over all working pressure.

If you take a look at this below linked topic, it will give you an idea of overall pressure, and pressures at the gas port. Keep in mind that the powder being used is standard burn rate, and if a slower burning pressure was being used, then the peak over all spike pressure would be closer to the gas port, increasing the pressures at the gas port as well.

http://www.ar15.com/forums/t_3_66/266108_How_it_Works__The_AR_gas_operation_and_how_everything_works_in_harmony_.html

Now lets get down to the unlock.

B/C carrier mass, recoil spring tension, and the amount of gas that the gas system see's, all play the Math part in how the system works.  As stated, the pulse of the gas system happens as the bullet passes the gas port, then this pressure starts to drop as soon as the bullet exits the barrel.

So at the bolt, we first have the gas system charge pushing the B/C back, which includes mass of the B/C, the mass of the buffer, and the spring tension.  Here, we are looking for enough gas pressure  force to full stroke the B/C all the way back, but at the same time since the bolt has to cam around to the unlocked position before the bolt lugs can clear the barrel extension lugs, enough gas pressure drop in the barrel bore before the bolt/barrel lugs clear each other so the spent case is not pressure welded to chamber so much that the bolt can not pull it out cleanly.

Again, increasing the mass of the B/C and buffer, and even adding buffer spring tension slows the initial movement of the carrier back at gas charge (micro seconds), which slows the unlock down just enough to allow more barrel residual pressure drop to happen before the bolt actual pulls the spent case out of the chamber.

So how does this all come together?

We have a round loaded for a over all 62K pressure.  
Since we have a gas system, then where the gun powder peak burn dwell happens down the barrel bore, will dictate what amount that the gas ports sees.   Since the rifle is based off standard burn rates, when you use slower burning powder to push heaver bullet down the barrel (while still staying in the 62K max pressure allowed), your going to have higher gas port pressures (peak dwell closer to the gas port). Since the math of how the rifle unlocks is gas pressure against Mass of the B/C and Buffer, and the tension of the recoils spring, increases these will slow down the bolt unlocking and begins to pull the spent case out of the camber (bore residual gas pressure drop) back into check.

As for why not just use the same powder burn rate for all loads, it does not work out this way.   The heaver the bullet, the slower the powder burn needed to get the bullet up to top speeds while staying in the over all working pressures,which increases the gas port pressure.  Same goes for lighter than normal bullet loads, with faster burning powder used, which means a decrease in gas system pressures instead (all the while both over all working pressures of both loads at 62K).

All depends now,

What does the primers look like on the  reloaded rounds that  did not blow a primer with these reloads/questionable rounds?

If the primers are screaming over pressure, then its time to pull the rounds down to salvage components and start the reloads over, since it could even be that the cases in question where not OAL trimmed correctly, and them alone that is causing an over pressure problem.