I think the bearing surface is short on the 62. To be able to fit it in a standard mag @2.26” most of the bearing surface is below the neck.It could be done. The new 62 gr is 1.055" long I read, the 77 TMK is 1.07", and those are frequently loaded to mag length, even as a factory round. But that would steal the attention away from their new 22ARC.