I agree with stokesrj I used the info from the link on my Grendel and a 223 AR. I made my own V-block with a piece of 2x4 and a router. Because the ejector roll pin is offset it is really hard to remove the pin without a v-block, also I bent 2 punches without it. I only pushed the roll pin out until the ejector was free because starting the offset roll pin is a PITA. You should have a spare available before you start doing this just in case. Other benefits to this are not having those deep gouges in the neck that can be seen in the 1st pic under your index finger and the brass not going as far. One other thing that may be causing this is too light a buffer but either way you will benefit from modifying the ejector spring.
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