Re: where to buy a break with 5/8- 24tpi threads
Brownells has several.
the Ops inc. brake , Shrewed , Gentry "quiet brake" and the KDF brake all com in the 5/8-24 thread.
Any of the custom makers should be able to make one to your spec as far as twist and size , the trick is getting it indexed so it sitts properly on the barrel.
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