I have my 5.56 lowers and uppers, but I heard you can mount a 300 blackout on a 5.56 lower.
Would this actually work? How many different uppers could I use? I heard that I could mount a .50 cal. Beowulf upper on my lower too, any truth in that?
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Worked great on mine😎
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Good to know! Thanks!!!
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I ran Lancer magazines
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Will regular 5.56 mags work? I live in Washington Socialist State and cannot get 30 round mags anymore.
300bo uses same circumference brass, bolt & carrier group as 556. I’ve had mixed results with some reg ar mags. Best results are with dedicated 300bo mags from Magpul(30) & Lancer(20). Haven’t checked out any comm block 10 rounders.
I think some other calibers have non-interchangable bolt carrier groups .50 beo, 6.5 grendal.
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I tried my 5.56 and it didn’t like them at all, went with dedicated 300 mags
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I do believe the only thing that has to be different to go from 5.56 to .300 blk is the barrel, although dedicated .300 mags may work better
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Last I checked Lancer recommended using their standard 5.56 mags with the lighter high velocity 300blk rounds. Lancer apparently makes their 300blk specific mags for the heavier subsonic loads.
I’ve had good luck with the standard 5.56 Lancers with the light and fast 300blk loads. They make 10 and 20 round mags as well as the 30s.
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