I built a P14 in .458 x 2" American. It is a single shot simply because I have not made it feed. I installed the magnum magazine box, but before I start cutting on the feed rails I would like a sggestion as to what specs to use. I don't have any other .458 to measure.

I have an x2 on a vz24 action which feeds very well. I am not home at the moment so I cannot measure for you but if you want to call my gunsmith and ask what he did to make it perfect I am sure he is nice enough a guy to talk about it.

Paul Grundman 707 7645744

He is off hunting sheep quite often or turkey or fishing or hunting mushrooms or ... well you get the idea. Just keep trying.
Frank