I am currently assembling 30 1964 Romanian military AK, these are prior to the vertical foregrip, they have had who knows how many full auto rounds fired through them all 30 kits are total all stamped matching parts, there is zero finish on exposed surfaces, the hardwood stocks all have "cheek" indentations were they have been used so much the wood is scrubbed into an indent, the lower HGs are finger grooved from wear, but all components are still within spec and If I were to assemble them as original (ie; full autos in order to use original fire control group parts) they would go right back to working fine.... 3 of them need new recoil springs as noted by bolt carrier marks on rear trunion (very faint but is an indicator the springs were getting weak) A semi auto AK properly assembled on a fully heat treated in spec reciever like a NODAK Spuds $55 econo will outlast you if properly cared for, these 30 rifles never got oiled or taken care of but the chrome bores are all still looking like new and the FCG parts while worn are still within spec....
I'm stamping the recievers for these particular rifles myself so as to maintain the originality as an Original reciever does not have the serial number on the reciever, I do fully heat treat them and the finish will be "antiqued" or worn to match the original reciever stubs etc... I bought these kits with this intention in mind..
I have one AK built on an Arsenal 1.6 mm reciever with a bulgarian parts kit that lives in my sand rail, is always out in the weather as It never leaves the rail (There is a lock welded to the vertical roll cage bar between the seats just for it to be secured, it can only be removed by destroying it) its been there for 4 years with an 6x42 POSP scop attached, the rifle originally was Sand blasted, then Grey parkerized then painted with O.D Green durakoat, there is maybe 30% finish still remaining on the metal, the scope has pretty much no finish left on it except whats protected by the butler creek lens covers, that rifle is always full of sand and has to be shaken out every now and then, it gets cleaned every 6 months or so in the form of a boresnake being pulled through it, the bolt rails get a coat of Remington dry lube... it will still shoot 2" groups at 100 yards and flips Coyotes or jack rabits anytime ya want...
An AK is so much tougher than any AR or G3 or even an L1A1 (metric fals don't have sand cuts so do me no good) that I don't think you will ever be able to wear one out.... not a Semi auto version anyway..
The key is to stick with a Rivet build don't let anyone talk ya into any BS shortcuts like screws or welding or "U" Drives etc.... use a quality reciever, and ya'll be good
Onmilo, where did ya come up with the info that they only last 20,000? I have a Registered full auto Chicom my Father brought back from vietnam in 1971 that I have put over 200,000 rnds through who knows how many the vietnamese owner put through it before my father "collected" it, I have Russian AKs with over 50,000 rnds through em still going strong and 100% in spec. Out of the 287 AKs both milled and stamped in my collection not one rifle has ever had any shaking apart, And 3 of those are NFA registered full autos. Ya must be thinking about an AR cause ya can't wear out a Semi auto AK they were engineered to endure full auto use in the worst conditions with the most minimal maintnence etc...
As far as the mags, I've got over 400 30 and 20 rnd mags never have had any problems except the one that I accidentally ran over while hunting yotes from the rail a couple years ago, if ya bend one then it will stop working. Living here in Arizona guns don't get pampered if they are "working guns" and the AK or an SKS is what ya'll find laying behind the seat or in the bed of most every ranchers truck... they look like hell but they always ALWAYS go bang