I finally have a Ruger 22/45 that works......
I bought a brand new Ruger 22/45 Mk III about a year ago and had nothing but trouble with it. The biggest problem was that every time I put a magazine in the gun, the trigger would not work. I would have to press it hard, then back off and press it again. Most of the time the trigger would work for the rest of the magazine, but not always. The sometimes-it-works-and-sometimes-it-doesn’t-work trigger did terrible things to my accuracy with it. It also had other problems, but that was the biggest.
I sent it back to Ruger with details of the problems. They replaced the magazine safety and sent it back. I took it to the range and found that it was still a problem, so I started reading on the Internet about it. Seems like a large number of people have had the same problem. And, they have a preferred solution.
I got some Mk II internal parts and took them to a gunsmith to install. I took a look at videos of the internals of the 22/45. Way too many parts for me to mess with. Especially hairpin springs. I hate messing with hairpin springs. What the new parts did was remove the magazine safety and replace it with a spacer. I got it back Friday and tried it this weekend. It works perfectly every time now and the accuracy is every bit as good as my S&W K-22. I am finally happy with it now.