There is a couple of things that come to mind. The bolts are considered a "wear item" at a lower round count. I've heard as low as 3000rds. I pulled all my bolts and replaced them with Young manufacturing bolts. They look rather stout. I keep the originals as replacements. I tripped over a deal for $45 on some other bolts back when the "plandemic" started. I forget where. There is a couple of MFR's out there that have lifetime guarantees. Don't ask me who. Maybe Primary Arms sells one of what brand I have no idea. There is a seller out there that sells the Young bolts "The Buffalo." I had bought several times from him when I first discovered Young's stuff. Young only sells a chrome plated bolt. They used to sell a phosphate coatedIs the 7.62x39 AR-type platform as reliable as the AK-47? How is the accuracy out of the AR-type platform?
Mags in my opinion are the biggest stumbling block for reliability. I have tried 2 different brands. ASC, and C-Products Defense. ASC's were garbage. I got an RA from them and sent all 22 of them back. They were going to "repair" them. 2 months later I called and asked what was going on. They sent me 22 brand new replacements in the wrapper. They were worse. The bodies wouldn't allow more than 14rds (30rd) and the follower would jam. The bodies were tapered in the curve. That was the problem. They claim on their website "Lifetime guarantee, we test every mag before we ship!" BS. I didn't bother contacting them about this totally different problem I wrote it off as a very expensive mistake. I sold 12 of them still in the packages to a gun show vender over the weekend. Maybe they had the same defect, maybe they didn't. I don't care. They sat in a box for a couple of years. A member on another forum had problems with his and trashed them.
I have had zero problems with C-P-D's.
As far as barrels I prefer the idea of at minimum having a nitride barrel due to the copper washed steel projectiles in most of the imported ammo. I have seen a chrome lined barrel being marketed. Can't remember who sells it. All 3 of mine are nitride 4150. 2 are 16" PSA, the 10.5" is from Alpha Shooting Sports. I know of shooters using BCA's and they are very accurate. I suspect without proof that many "other brand" sellers are selling BCA's.
My first PSA has touched 3 Tula at 65yds with a $20 red dot. I have 2 Primary Arms 300black/x39 ACSS scopes to zero in. Can't shoot the steel at indoor ranges. Need a partner to keep an eye on my gear at the outdoor ranges.
Small Arms Solutions has a great comparison on the hybrid carbines out there that use AK47 mags. PSA won hands down in all categories. They beat the big money CMMG mutant. IIRC it was mag picky. Mag compatibility is a factor. Not with PSA.
Draw back to the hybrids is no bolt hold open. Maybe the Yugo mags will? I have no idea.
A standard AR lower works with the AR uppers. Go to a H2 or heavier buffer. I have gone all the way up to a 6.1oz. However some run .308 springs. I have some. Haven't tried them yet.
All of my barrels are mid length gas. They recoil a bunch harder than 5.56. Many commercial uppers are carbine length. If you are recoil sensitive you might want to shy away from them. Then again playing with buffer weight, and the .308 spring can help tame them.
Any questions maybe I can answer them after work, or during depending on if I am sitting getting loaded or unloaded.