RPR Barrel Threads (5/8x24 ???) To Suppressor

GS455

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Minuteman
Jun 14, 2013
122
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Nashville
Just tried to test fit a HUXWRX 5/8x24 direct thread adpter onto my Gen II RPR (in .308). Won't go a half turn. Tried it on my x39 RAR and fits beautifully.

Can't find anything anywhere that indicates the barrel thread should be other than 5/8 x 24.

I've got a note in to Ruger tech support but this is driving me nuts.
 
Could be just a very tiny bur. I had a Remington like that, it went 3/4 of the way on and got tight, I put a wrench on it and worked it back and forth slowly until it went against the shoulder, everything after that threaded on fine
 
Impatient !!! Ended up cleaning, applying a little grease and slowly chased it on a bit at a time. Seems to have cut a skootch deeper valley in between the threads but they are still "proud" and don't look to be stripped.