I personally owned a Ruger Mini-30 Stainless Ranch rifle for several years. Because of the cheap ammo, I shot it all the time. Accuracy was just terrible. First in the wood stock, then in a Choate stock, then with a shorter 16" barrel and Choat flash supressor... Never did anything to improve accuracy.
I would get a 12" paper plate and draw a big 1" red dot in the middle and place it on a saw horse at 100 yards. Then, with a Tasco Compact 2-8x32 scope mounted on it using the factory mounts, I never ONCE actually hit the red dot. I'd hit the paper plate every time, but it was very disappointing.
My buddy had an SKS, and he could hit all around the red dot in what actually resembled a "group", while I never knew if I was going to hit 3" high, 2" low, 4" left, or 6" right of that dot...
Ammo was just whatever surplus stuff was cheap back then.
That was my one and only non-.22 rifle back then, so I wasn't at all happy with it. I wanted it to be a hunting rifle, SHTF rifle (hey, I was 19
) Sniper rifle, etc. Accuracy was terrible, and I never found a single 20 or 30 round mag that would work reliably. With the 5 round factory mag, it was 100% reliable.
Now that I have several rifles that fill different roles, I did consider buying another one just for fun, but for the price, it's still not worth it for me. I will probably end up with a Saiga since I don't care about full cap mags for it any more than I would have wanted hi-cap mags in the Mini.