CZ 527 18” threaded

[riuma]

Unclear what is the issue that you are having with the thread pitch. The 1/2"x28tpi is the industry standard for all calibers .223/5.56 and smaller. Whereas, 5/8"x24tpi is used for calibers 6mm and greater. Once you get to the big boys Cheytac/BMG it is a larger thread.

If your rifle is chambered in 6.5 Grendel then you want a 5/8"x24tpi to give you enough wall thickness to preserve the rifle bore while still allowing for threading.

What is the caliber of your CZ527?

I'm guessing it is a standard American 6.5 Grendel that was threaded 1/2-28, and for which the previous owner used an adapter. I was faced with the same situation and opted for buying a CZ Varmint, already threaded, instead of cutting down myfavorite hunting rifle.~Riuma