No ....only have added the carrier weight to a standard carrier....I really think you're going to put a lot of stress on the upper with a skeletonized carrier just to light....you need to remember the upper and standard carrier were designed for the 5.56 shooting 50-64 gr bullet some more or less.... 450 Bushmaster you're using 160-300 gr bullets ....put a lighter carrier and you're going to start beating parts up....not that it will brake the first or even the tenth shot but its not going to be good over time.....
I use Hoot's carrier weight system on all 450 Bushmaster's I have build.......
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