(This is a revised version of a post I made to the Backwoodsman mailing list a little while ago.)
I have an early-1980s vintage Mini-14 that I bought used a few years ago. One thing to keep in mind about the Mini-14 is that it is fundamentally a sporting rifle, although it is suitable for civilian
(including law enforcement) social use.
The design of the Mini-14 is relatively simple, especially when compared with an AR-15. Field stripping it results in a few large subassemblies, with no small parts to keep track of. The gas system is very simple: the piston is hollow and stationary, while the cylinder is a matching whole in the op rod (IIRC, Ruger calls it the slide).
Due to the simple design, clearances that aren't too tight, and the ample amount of gas vented into the system, Mini-14s tend to be extremely reliable, even if neglected. I have found that if you don't wipe down the piston and cylinder with a *light* coat of oil after shooting, a little bit of rust can develop and freeze the op rod in place, requiring you to whack it to open the action.
Mini-14s may not stand up to outright abuse as well as true military rifles. That's neither here nor there, just a matter of selecting the correct tool for the job.
Reliability is contingent upon using good magazines. During the Assault Weapons Ban 1994 - 2004, good mags holding over 10 rounds could be very difficult to find. That's no longer the case. The best magazines are those from Ruger, followed by pre-ban PMIs, then new-production Pro
Mags, which surprisingly enough, have a good reputation. Ruger officially doesn't sell 20 round magazines to Joe Citizen, but they are available for about $35 - $40 each if you look around a little.
Another way to ensure reliability is to use grease to lube the Mini-14, instead of oil. The Ruger is descended from the M-1 and M-14, so I lube mine accordingly, with grease. This stands up better than oil to rain and heat.
My Mini-14 will eat anything I feed it, including Wolf steel cased ammo that causes malfunctions in my Colt AR-15. Note that if you shoot steel cased ammo, make sure you clean the chamber well afterwards. Steel cases don't obturate as well as brass, so the chamber will often get dirty, leading to failures to extract. This advice goes for any gun in which you shoot steel cased ammo.
The Mini-14 has a thin, whippy barrel that causes groups to open up when it gets hot. Adding a muzzle brake or flash hider can dampen the whip. Chopping the barrel to 16" achieves the same effect, I'm told. Doing so does slightly reduce velocity, however.
I really like mine. I'd prefer an AK or a FAL if I was heading into battle, but I'm not a soldier. For a civilian like me, the Mini-14 is great. It's rock solid reliable, accurate enough for what it
is, and fun to shoot. IMHO, new Mini-14s are too expensive at around $600 MSRP. But you can pick up a used rifle for about $325 - $400, which is a reasonable price. For a hundred or so dollars more you may be able to find a used stainless steel Mini-14, which when combined with a synthetic stock gives you a very weather resistant rifle.