Quote Originally Posted by alpining
Hi all - I'm trying to buy a stainless barrel nut from Numrich, but their descriptions don't state whether the part is smooth or splined. Does anyone here have the details on which particular models have the smooth nut? I want the splined nut, you see... For example, they sell separate items for model 12FVSS and 16FCSS but don't give any details. I THINK the 12FVSS has a splined barrel nut (and the 16FCSS has smooth), but I'd like to be sure.
I believe all of the newer Accustock guns with the bottom mounted bolt release also have the smooth nut. The difference between the 12 and 16 versions may be that the 12 is blued and the 16 is stainless steel.

BTW, the grooved nut is a direct substitution for the smooth one.