NEW polymer 10Round AR-15 magazines

[n-tactical]

10 round AR-15 magazine with anti-tilt follower and anti-corrosion coated spring. $13 each.
Now taking web orders.

http://ntactical.com/ntac-10-round-magazine.html

Assembled in California.

[CRTguns]

Is there a rib moulded inside, to hit the cartridge shoulder? I ask because there are rounds out there that do well with the rib gone. That would be a good thing for stuff like... 416 hushpuppy, 338 wisper, 358 spectre, 35 gremlin etc...