They are all a much of a muchness Ken. Brake design has not really progressed from WW2 arty apart from angles, number of baffles or ports.
A decent triple port brake without to many sharp angles and edges to gas wash, is all you need for a 7mm rem mag I reckon.
I have a couple off Abe and they are well made and priced. I have a spare triple port one I could send you for nada if you want it. I will bring it back here to Oz in a couple weeks.
It will fit a standard profile blaser barrel as long as it has not been threaded yet.
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