I've never seen a picture of a Surefire with a blast baffle worn out, except for the picture below. There are a lot of baffles in a surefire can that are a lot more thin than the rear one, and they probably do wear out, but the rear baffle probably won't under any normal use.
The cutaway image of a Surefire I was told was cycled 200 rounds in around 3 minutes on a UICW 6.8 SPC and every baffle in front of the blast baffle looks worse than the blast baffle. The forwardmost baffle looks like it could be .670" aperture ID. This kind of supports my theory that the front baffles in a Surefire will wear out first.
These threads that kind of operate on the assumption the only baffle wear that matters is in back, are kind of misguided. Our Recce cans had the same baffle thickness from front to back until this last year when we put a little extra thickness on the first baffle while leaving all the others the same as they had been. That move was not for any reason other than the picture threads like this. The 200 round test didn't yield the Recce 7 baffle at all- it was totally normal in shape, and had only minor peening of the aperture.
These are old cans and this test was ancient history (like 10 years old).
The other picture is of a basically light use core for a comparison of what the core sort of looked like before the test. (both of these cans are the older mig welded cores, not the laser welded cores, but as you can see the welds didn't fail). We developed a Recce 7 that passed the 200 round UICW test with no baffle distortion (full disclosure, our first test destroyed a tig welded can due to a weld failure at around 190 rounds [this was a tubeless RECCE 7], and our welds were strengthened by heating up the parameters and increasing fusion depth which was always difficult with TIG because of all the heat tig generates. Even with 4 quadrant CNC welders with like 50 parameters, TIG is really tough to program and it's just not ideal. Getting ideal penetration is not tough with laser welding, and at that point the revised can to the new tig weld spec passed the test that had reportedly destroyed the surefire and an AAC SDN-6 [I was told the AAC suffered broken baffle welds]), but the recce 7 wasn't purchased, so the test only improved our cans and cost us money without making any of the companies jack shit.
The Recce 7 looked like it could have done this 200 round test 10 times before being considered worse for wear. The UICW was overgassed for arduous conditions in the desert, so it was not an ideal suppressor host and cyclic rate was high like a micro uzi, but our cans also had more backpressure then and we were running a 6.8 specific bore in that can which probably didn’t help. Our eco flow cans would have probably run a lot better now on the same gun.
The post isn't intended to say any brand sucked. The UICW is like near .308 power cartridge in an 8" barrel. It is rough on cans, and most cans aren't overbuilt enough to do something that unorthodox. 8" 6 8 SPC UCIW Suppressor Durability Test