300 Blackout magazines

[dtom29]

Brownells mags work well also. They have an excellent follower and finish. Rapidly becoming one of my favorite mags for both 5.56 and 300 BLK.

[-k-]

I think the 300 BLK would benefit from a purpose built mag that has the front rib at the neck/shoulder. I think it's unlikely a barrier blind subsonic bullet design can be made with a shape for optimal feeding in a 5.56 mag.

That said most people don't need 300 BLK specific mags. Many standard 30 cal bullets can be loaded to a length that feeds well out of unmodified 5.56 mags, plus there are the 300 BLK specific designs that fit perfectly.

[Dr.Phil]

I think it's unlikely a barrier blind subsonic bullet design can be made with a shape for optimal feeding in a 5.56 mag.

Has already been made...

Lehigh Defense has been fairly active on this forum and mentioned that one of the attributes that they discovered while testing the new 300 BLK 194 Grain Maximum Expansion design was its "barrier blind" tendencies.
The funny part is that being "barrier blind" was not part of the design, it just worked out that way.
This bullet is truly an impressive piece on engineering and it provides additional capabilities to the 300 BLK AR platform.
With an MSRP of $77 per box of 50 projectiles, or $50 per box of 20 loaded cartridges, it has a price tag that matches its capabilities.
But unlike many other 300 BLK specific projectiles, at least they are in stock and shipping at this time.
viewtopic.php?f=151&t=78878

[tallburnedmidget]

just to clarify, i am not wanting to argue a point from the above 2 posts, i really just am not understanding.

.308 bullets are not designed for feeding out of AR mags. Also feed ramps are built for feeding .224 bullets not .308 so rounder larger .308 bullets can have trouble with the ramps (my powder coated cast do). Additionally most .308 bullets are not designed to expand at the slower 300BLK velocities very well.

There are only about 5-6 bullets that I can think of that are designed that deal with with all of the issue I mention.
-Lehigh Defense ME
-Lehigh Defense CF
-Lehigh Defense CC
-Barnes Tac-TX (300blk)
-Sierra Match King 125gr (300blk)
-I want to say there is a subsonic SMK built for 300BLK as well but not positive, and I may be missing some others

All other .308 bullets are not designed taking into consideration the issues I mentioned above. Hope this helps

[Overton-AR]

I really like the Lancer 7.62x40 mags. They are made for Wilson combat by Lancer and they feed 300BLK very nicely. Even the FAT bullets that would require rather DEEP seating to use in standard mags. I bought them for use with my heavy cast sub-sonic bullets. They are VERY 300BLK friendly. I could have gone with the DH 300BLK mags, but I am not a fan of 30 round mags and DH isn't making the 300BLK mags in the 20 round variety.

[mrgein]

what is meant by the term "barrier blind"

[Dr.Phil]

what is meant by the term "barrier blind"

= Maintaining trajectory and terminal performance after penetrating a barrier such as a door, window, or wall.

[-k-]

Has already been made...

Based on the shape in the pic I don't think those can be loaded to mag length and not pigeon toe the stack.

[Nic56]

I really like the Lancer 7.62x40 mags. They are made for Wilson combat by Lancer and they feed 300BLK very nicely. Even the FAT bullets that would require rather DEEP seating to use in standard mags. I bought them for use with my heavy cast sub-sonic bullets. They are VERY 300BLK friendly. I could have gone with the DH 300BLK mags, but I am not a fan of 30 round mags and DH isn't making the 300BLK mags in the 20 round variety.

So, those work pretty well eh? All my AR mags are .223 Lancer mags. They do fine, but it would be nice if there was something a little roomier for the big bullets.