FNC stands for Ferritic Nitro Carburizing and is a surface treatment that makes the steel turn black. Since we use Stainless Steel for our barrels, it is primarily cosmetic. But it does have the added benefits of increasing the surface hardness of the material, increasing lubricity, and enhancing corrosion and wear protection.
For best accuracy, your barrel tenon should slightly interfere with the bore in your receiver (by .0002-.0005). For this reason, we have left the tenon slightly oversized so it can be fit to your specific receiver. Instructions are included with each barrel.
The .22 Bentz chamber is a .22LR chamber that was developed specifically for auto loading .22 rifles. The .22 MATCH chamber is too tight for autoloading rifles so the Bentz chamber falls between the SAAMI MATCH and SAAMI SPORTING chambers for .22 LR.
We do not recommend using "Hyper" velocity .22LR (ie: CCI Stinger, etc.), this increased chamber pressure can cause premature wear or damage to your receiver or internal parts. We don't advise going above 1400 fps.
Yes, sub-sonic ammo can be fired through your barrel, but the lower chamber pressure may not fully cycle your action which can cause jamming.
All of our barrels are drilled to near nominal size, reamed, button rifled, then stress relieved.
Always clean a barrel from chamber to muzzle. We like using wet / dry patches with Break Free CPL. A .22 caliber Bore Snake is also a popular option.