Clean it just you'd clean any other rifle/pistol after using corrosive, it'll take a bit more time. I use only corrosive in my milsurp firearms, well, expect for 9mm pistols. If you clean it thoroughly and on the same day there shouldn't be any problem. Some people use warm water with soap to wash out salt from the barrel/parts, I use Windex. After that's done I just clean and oil as per regular maintenance rules.
It's chambered in 223, so only non-corrosive. I'll bring it in to a gun smith to see if there is anything that can be done on the trigger and have him look at the crown. I might just have to try hand loads to see if that makes a difference.
Like other people said, 3-5 is normal for that rifle, your scope might be playing games. I fired plenty of Vz's, mostly with milsurp ammo, they are all pretty similar in accuracy, a bit better with decent scope though. At least one I own is pretty close to what you have when fired with ARMS BUIS.
Yup. Looks like the 3+ MOA is what it is. I thought it might have been the scope but I tested the Vortex 1-6x optic on my other rifle platforms and it works consistent on those other rifles. I'll have plenty of time to try out some hand loads this winter. You know how it is. When all your other rifles are all 1MOA or better, you want it all.