Flush Bottom Metal

[HokeyPokeyKid]

Does the magazine body have any internal ribs that might affect the function of a round that has a longer body than the Grendel.
For example, a 6.5 carcarno with the shoulder set back 6 or 8 mm and necked down to 20 cal or 6mm.

The magazine has no internal ribs only a draft angle to keep the rounds pushing upward with even pressure, so if the case head is close to the Grendel or 7.63x39 you should be good