I have Ruger MK IV's and love them. I've been shooting precision pistol for the last few months and they shoot much better than I'm capable of right now. One of the options for the MK IV Target comes from the factory with a threaded barrel & a very basic compensator. I've only ever seen it in the blued finish not stainless. I have one that Turnbull Restoration did a custom job on and you can't even see it's threaded unless you look really closely. You can always have someone crown and thread the barrel after market too. It's not that expensive.
As others have said I highly recommend the Volquartsen accurizing kit. Redoing the trigger, hammer and sear assembly along with tuning the bolt will run you about $150 if you do it yourself or they will install everything for you for $100. Turn around was about a week when I had mine done.
Agreed. Made a huge difference.
Trigger wasn't bad before, but this made it great