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300blk out Mags

Just to see if anything is out there, does anyone have any 300blk out mags they are willing to part with.
I live near South Point


LEGEN...wait for it... DARY!
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Most 300 Blackout ammo works in most 223 magazines. I only really got into problems with the big 40-rd Magpul.

I use 20-rnd magazines most of the time for everything, and I've never had an issue with Blackout ammo in any of them.

That said, I do have some 20-rd mags marked for Blackout, and they also feed 223 flawlessly.
Yea went to the range the other day and I was using my regular 223 mags (pmags) and it wasn’t feeding, every other round 🤷🏽‍♂️
how many do you have?


Geth Prime
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Weird, but also not so, depending on what load you are using.

I can stuff 20-22 rounds of 200-220gr subs in a G2 30rd Pmag without issues. It gets dicey after that. Skinny supers? (That said, there is an acknowledged issue with standard PMags and some 300BLK rounds)

20round Pmags, no issue.

Lancer Mags, full load. 20 or 30 rounds mags. No issues.

Magpul 300BLK PMags, good to go.
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Geth Prime
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If I remember correctly the modifications that Magpul made related to the little ribs on both sides at the top of the mag, that corresponds to where the shoulder would be on a 223/5.56 (as well as thinning down the central rib thickness), which would not be in the same place on a fat 300blk round.

I think there is a video out there somewhere on modifying older PMags to 'fix' the issue. If you've got extra PMags you could try the modification on one. I'll see if I can find the vid.

As a side note, while 300BLK Pmags are no where near as cheap (on sale) as you can find regular PMags, Primary Arms does get them down to $10.49-$11.99 on sale now and then.
Thanks for all the info I’ll look for the video as well! Yea I’ve been shopping around on primary arms and botach for the mags