Untrue. If the trunnion of the rifle is pressed in straight and the barrel is pressed in with sufficient precision, typically through the use of laser levels, AKs are capable of the same level of accuracy as an AR. The plant that builds a particular rifle has everything to do with it. If your barrel is pressed into the trunnion with .0002” of runoff, for example, you’ll be looking at about 1.5”-1.75” groups at 100 all day. I build them. People buy cheap junk CE they arms and thing that quality applies to the entire AK family. I use AKs chambered in 7.62x39 almost exclusively and it’s minute of chest all day long at 350 if the builder goes the extra mile. Rifle dynamics has a model that will do 7” groups at 650 yards, which I refused to believe until I saw it myself. It’s all about building the rifle part by part on a 1:1 ratio. Anything less will result in subpat accuracy.
A well fitted out AR15 with a 20 inch medium weight 1-8 twist low-end broach-cut match barrel (Say a Wilson or a Douglas barrel) will group with M262 ammunition ~1 MOA range for ten shots @ 300 M. With a good cut-rifling heavy barrel, say a Schneider or a Krieger, it will do 10 shots around .65~.7 MOA consistently @ 300 M with better lots of M262. Both rifles with some sort of float tube.
The Army SDM rifles based on the M16A4 could keep shots in a head sized target at 550 M all day long with M262.
An average rack grade M16A2 out of the weapons pool with poorer lots of M855 will group 10 shots on the order of 15 inches at 300M. With M855A1, the same rifles will group 7.5 inches at 300 M, worst case. Average lots show 6.5 to 7 inch 10-shot groups at 300 M, though M855A1 is kind of hard on the bolts (much reduced life).
The chap who did the AK test above used the Yugo M70, which has a thicker action body and shoot better than an average AK. Same is true of the Saiga, they are known for superior accuracy using a the RPK receiver stamping, which once again is more rigid than the standard AK action body.
The average spec for an AK/AKM with the standard receiver stamping thickness was 4 shots in 15 cm (5.9 inches ) @ 100 m.
In my time of running a rifle range for competitive matches I have seen any number of skilled riflemen come up with a AK to try their hand at the NMC, and all have gone away with their tails between their legs, even on reduced range courses. Simply stated a standard AK has difficulty keeping 10 rounds in 6.5 MOA @ 100/200 yards and almost all of the rifles that showed up showed a marked tendency for the point of aim to shift as the weapon heated up. They are much poorer then M1 carbines, which really were never very good.
I note these resulted were recorded by NRA rated Experts, Masters and High Masters, folks who rally know how to shoot from position. Oddly enough these many folks have never found AK production rifles that can be depended on to hold point of aim and group 10 shots in under 2.0 MOA.
Meanwhile the Internet if full of Billy-Joe-Jim Bobs who have an accurate 1 MOA WASR AK. right......
Not denying the AK could be accurate, especially in a custom build, just pointing out what is out there in most folks hands is nothing like the armchair shooters posit.