Oh, well that's different. If you got a can for it I totally get it and I think that caliber is easier to suppress than mine is. I'd like to just port the barrel I have, it's not threaded. Something to tame the recoil. I wish I still had the short video we shot of us firing that damn thing on burst. It was actually kinda funny. Nobody could really control it. So I'd get a brake for when you're not using the can for sure. Half the fun with these is firing the full power stuff. You'll get a kick out of it for sure.
I'd also talk to someone about firing full power ammo and subs in the same rifle like that and see what they say about cycling. That's the only real concern about those I remember, cycling, so if you can avoid any problems that'd be in your favor. Hopefully someone with a .458 who does the same thing will chime in. You could also put it in the suppressor section and see what turns up.
I guess I was on the front end, but what happened was it was the tail end of the Cliton ban and after almost ten years of bullshit, engineering turned towards smaller compacts and big bore everything else. There were .50 Glocks and 1911's coming out, Beowulf, SOCOM and a few others. If you couldn't have 30 rounds then damn it, the 10 you can have better be as big as possible. That was the sentiment. 9/11 happened too and every mfg. on planet Earth was sending us free gear. Free gear! I mean good stuff too. KAC, Surefire, AA, etc., etc. First Magpul mag I saw was a case of freebies this squad leader asked for. Call or send a letter and a sample was on the way. Wear BDU's to a gunshow and you'd walk away with some free stuff too. It was nice companies helped soldiers out like that at that time, there wasn't any real new gear around then. The ban ended, the wars continued, tons of new stuff came out, and everything went back to a new normal.
I forget where I saw it or exactly what it was, but it's like a .458 but in an AR10 frame and it'll blow the doors off the SOCOM and Beowulf, and it'll handle some heavy subs too. I wish I could remember what it was. Kinda like a .450 Marlin or a .458 Win. Magnum and it was touted as the most powerful AR10. Used regular unaltered mags but I think the capacity was diminished some.