I am running Accurate mags on my edge build. They take 3.79" col, it is the 3.85" they list on there website. I just pressed out the inside shoulders on the mag and tweaked it a little. It would probably be easier to just mill them out but I did not want the open slots in the mag. Its not quit done but the mag and feed work perfect.
I looked at the xlr stock and it should be a good one for an edge build. If you do not have a ultramag action you can have the rear of the mag opening opened up to feed the longer round.
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[img width=600 height=400]http://i16.photobucket.com/albums/b23/tule-man/IMG_1419a.jpg[/img]
3.79" COAL
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