Looked at it on Savage's website (I'm surprised they'd call any rifle in .223 a Scout), looks like it might be an indexable brake.
Whether it is or not doesn't really matter, it's put on with either threadlocker or Rocksett.
I'm sure someone here knows which; threadlocker will need a propane or MAPP torch and heat to 500 degrees. Rocksett is unaffected by heat. Hang the rifle muzzle down with the brake in a cup of water, overnight.
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