If you think your misfires are being caused by poor ammo, it may very well be your firing pin. A quick swap out with a properly formed and finished firing pin can make it all go away.
I've shot Marks for all three generations, no question, this new Mark III sucks. Not only did Ruger scrape the bottom of the barrel with in Attorney Model III by way of a ridiculous chamber indicator, no hammer drop without mag, no slide without mag, poor magazine drop and weakened hammer strike, and more new parts than a Pattaya barmaid...but the firing pin now shipping with every new Ruger is nothing short of complete crap. If your firing pin looks like the one on top and you spend more time with your hand on the slide than Fred Wesley then read on.
I finally threw in the towel and bought a Majestic Arms firing pin. No misfires....none, over.
Half way down the page...
http://www.majesticarms.com/id10.html
I've shot Marks for all three generations, no question, this new Mark III sucks. Not only did Ruger scrape the bottom of the barrel with in Attorney Model III by way of a ridiculous chamber indicator, no hammer drop without mag, no slide without mag, poor magazine drop and weakened hammer strike, and more new parts than a Pattaya barmaid...but the firing pin now shipping with every new Ruger is nothing short of complete crap. If your firing pin looks like the one on top and you spend more time with your hand on the slide than Fred Wesley then read on.
I finally threw in the towel and bought a Majestic Arms firing pin. No misfires....none, over.

Half way down the page...
http://www.majesticarms.com/id10.html