Personally I would go with Savage 10PC because it has a shorter barrel - Of course the longer 10FCP could easily be shortened when threaded To answer your question - both rifle barrels have more than enough OD to cut 5/8 x 24 TPI. My 10PC is chambered for .223 and not threaded but I have 6 other rifles and pistols that are and i would strongly suggest you have the suppressor manufacturer cut the thread since all 5/8 x 24 threads are not equal
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