I don't know if that's out of spec or not, but my AR was long throated as well. Can't recall the exact measurement, somewhere in the 2.3ish range. Unless it's a bolt gun or a high end barrel most have room to play with. My understanding of this is so it can accept a wide variety of different bullets. The 69gr Sierra's are a pretty long bullet. But your OAL in a AR is limited by your mags. I know there are some AR mags that allow longer OALs.
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