I have had an Omega for a while and haven't had any complaints. Had to send it in once because it got so dirty it was noticeably louder, they replaced the core at no cost.
I've run it from a 10.5" SBR to a 22" WM with no issues.
My guess is Silencerco probably isnt going to give you the ok for RUM based on a quick look at how much powder they take.
Some companies like TBAC would give you a yes or no if you gave them specifics for a caliber that was rated such as your load, barrel length, etc.
I asked a question like this about 300 Norma when I got mine but SilencerCo wouldn't do the same deal that TBAC would. No big deal, just a heads up on experience I've had.
Off the top of my head I cant think of any rates for RUM but I also havent shopped for one in a while. Might have to look at 338 cans for that.
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