Somewhere between 250-400 depending. While they are good guns they are not AR's in the accuracy department. Even with a scope expect minute of paper plate at 100 yards. (give or take) Due to the long, thin barrel the accuracy tends to wander as the barrel heats up. They are also very dependent on good mags to run well and a factory 20 rounder will still cost $50. Great truck guns.
All that being said I wish I still had mine. Tricked out stainless with a Chote pistol grip stock I traded it for a Romanian AK and 1K rounds of wolf. AK shoots great I just never warmed up to it.
I have been thinking of selling it. I have maybe shot it ten times in the five years i have owned it. I bought it brand new and was going to use it for coyote hunting and never ever got into it. I look at it this way: "If you don't shoot it, then buy something you will"
I have two Ruger Mini-14's. Both have 185 series Serial Numbers for the 1 in 10 twist barrel. One is set up for Coyote Hunting (and it has worked very well for that) and the other is set up as a Tactical Carbine. The one setup for Coyotes has a Barrel Harmonizing Muzzle Break and a GLass Bedded Stock. It will give Sub 1 inch groups for the first 10 rounds which is generally more than I need. The Tactical version gives groups of 3 to 4 inches at 100 yards. Not Great but OKay for Combat. For the Hunter Magazines I use the Factory 5 or 20 round Boxes. For the Tactical I use ProMag 30 round Thermolds. BTW, barrel re-crowning will enhance a Mini-14 or Mini-30's accuracy very nicely. (I have a Mini-30, as well!)
Value may depend upon which Serial Number Series you have, to some who know the Mini-14, like myself. I value the 185 Series and before for it's 1 in 10 twist barrel as it will shoot most bullet weights up to 62 grains, as will the 189 Series, which has a 1 in 9 Twist barrel. The 189 and later Series Mini-14's will also handle bullets up to 75 grains. The 187 Series which has a 1 in 7 twist barrel is only good for bullet weights of 62 grains and higher, and best avoided.
Most used Mini-14's are in the $300 to $400 range, depending upon condition.
My advice to any of you planning to sell your "evil" assault rifles is not to do it! Depending on how you think the elections are going to turn out, it would be wise to stock up now on whatever is on your wishlist. That goes for high cap magazines as well. By the way unless the democrats nominate Satan for their president I am preatty sure they will win, and if that happens say hello to a permanent assault weapons ban. I didn't mean to get all negative back there but I want to drive home the fact that you should keep that mini-14.