From what I am reading a barrel with a .311 chamber is the best for Wolf ammo.

What barrel would everyone suggest for a 8"-10.5" barrel?

I use a Colt barrel and have no issues.  You certainly don't want to run lacquer or poly cases in a chamber that is too tight.

Best how?  I have PSA nitride and Kak CHF in x39.  They both handle wolf fine.  Never had a single issue with either.
As far as accuracy, its luck of the draw if a given barrel will like a given ammo.  I wouldn't go spending a bunch of money trying to find any barrel that does 0.5MOA with steel cased wolf x39 or anything like that.

I have a $60 Bear Creek barrel that’ll do about 2.5 MOA w steel case and about a quarter to half MOA better with Hornady Black ammo at three times the price (or maybe more; don’t remember what I paid).  So along the lines of what the poster above me wrote, don’t spend a bunch on a barrel and expect fantastic groups from cheap ammo.

https://www.cheaperthandirt.com/product/new-frontier-ar-15-16-heavy-barrel-762x39-110-twist-threaded-5-8x24-tpi-m4-feed-ramps-black-finish-7-bbl76216.do

here you go, used in two builds, correct bore and accurate

AR Stoner here. Reliable, accurate, inexpensive.

Keep in mind that factory 7.62x39 steel case from Russia runs in the low 40,000psi region.

They aren't throat-cookers by any stretch of the imagination.

How are the Faxon barrels? Are they .311 or are they .308?

What about KAK barrels. It looks like there is a pretty large price difference between their value line and their stainless.

Love my Faxon 10.5” 7.62X39.

I have a 10.5” Faxon barrel that has been very accurate e with Tulsa steel case 154 gr SP ammo. I got a 2-3” group for most of a 30 round mag at 50 yards with a 2 MOA red dot and 3X magnifier. Very impressed so far.

I have 2 Faxon 7.62x39 barrels, 14.5", that I use only with the cheap Wolf steel-cased FMJ.  very happy with the results, they run fine.  one of them is regular DI, and the other has a piston conversion kit.   just used for plinking, range fun.

I have the KAK 11" value line 7.62x39 barrel on a pistol upper.  I get about 1.5-2 moa at 50 yards shooting wolf and Red Army thus far.  I have the barrel mated to a KAK upper.  I have had to reshape the feed ramps quite a bit to get it to feed smoothly though.  M4 feed ramps do not work well with 7.62x39.  It is still very much worth the $85 I spent on the barrel.  I do have and run the KAK BCG and it is suppose to be built for accuracy and durability when using steel cased ammo.

speaking of KAK Value-Line, I also have one of those, the price is too hard to pass up.  got the 16" carbine barrel, and had it shortened to 14"+ with the perm-attached muzzle device to 16.1".  I found it to be significantly overgassed (even with H3 buffer), had to restrict the gas port with screw-in orificed set screw in the A2 FSB.  but the shape of the feed ramps on mine were fine as-is, work perfectly with my M4-ramped upper, CPD/ASC mags, Wolf steel-case FMJ only.  I did polish the barrel extension feed ramps (felt cone, polishing compound), but I do that for all my assemblies regardless.

had a kak on a 308 build and it was a nice barrel, not over gassed, reasonably accurate for 125.

the link I posted up top is real deal here boys, those barrels are outstanding for this caliber

 This.  Wolf is great plinking/cheap stockpiling ammo, but I wouldn't expect miracles.

0.308".  My 16" lightweight shoots steel case ammo well, Barnes TSX handloads very well.  Have not tried 0.308 bullets yet.

Faxon is great
I have a 12” that hits 8” steel at 100 yards with a $39 red dot from cabales
Look for a Young MFG bolt

The USA standard bore size for 7.62x39mm is .310". Occasionally some barrel makers use the ComBloc standard 311".

Surplus steel cased ammo shoots so poorly it won't make any difference which one you buy. Most ComBloc barrels actually measure .312", sometimes bigger.

I own a DPMS 20" and a 16" from a vendor who cannot be named (ER Shaw blank). Both uppers are very accurate with Sierra 125 grain .311" Pro-Hunter bullets seated @ 2.200", IMI or PMC brass and either:

24.5 grains of H4198

or 28.0 grains of H322.

I don't/won't shoot steel cased ammo unless somebody gives it to me. If it's free, then I'll shoot it.

The only surplus ammo I have ever shot that was acceptable was brass cased, Berdan  primerd, Yugoslavian M67 ball. It is corrosive and requires immediate cleaning after use. 2" groups @ 100 yards from a scoped AK. Everything else (steel cased) was closer to 6"+ @ 100. In other words, absolute junk.