Grendel mags? or 6.8 mag?

[VASCAR2]

I've never used 6.8 SPC mags but I have ASC & C Products 5 & 10 round mags which have always worked. My 5 round magazine only holds 4 rounds and my 10 round only easily accept 9 rounds. I don't have or tried any of the C Products Defense mags or the new 25 round Elander mags. I have never tried to load my cartridges that long as my chamber will not accept cartridges seated that long.