AXMC doesn’t need the adapter. The new mags are made the same as the AXSR mags and require no adapterNever have had an issue with mine running 6.5CM. It clips in like a bank vault meaning there is zero play whatsoever. As another poster commented, it’s just another piece of kit to keep track of. Other than that, it works flawlessly. That is why I said earlier in this thread that if I was starting from scratch I would get the newer ASR mags because that would alleviate the need to even have an extra piece of kit to keep track of. The mags work in the adaptor flawlessly from my experience and I have 5 308 mags that I alternate between.
At least the mags I used for 6.5 in my AXMC
If you want to share short action mags with another rifle then the adapter would be needed. But there’s specific short action round mags made for the platform that I used